African Americans are an ethnic group of Americans with total or partial ancestry from any of the black racial groups of Africa. The term refers to descendants of enslaved black people who are from the United States. Black and African Americans constitute the third largest racial and ethnic group in the United States. Most African Americans are descendants of enslaved peoples within the boundaries of the present United States. On average, African Americans are of West/Central African and European descent, some have Native American ancestry. According to U. S. Census Bureau data, African immigrants do not self-identify as African American; the overwhelming majority of African immigrants identify instead with their own respective ethnicities. Immigrants from some Caribbean, Central American and South American nations and their descendants may or may not self-identify with the term. African-American history starts in the 16th century, with peoples from West Africa forcibly taken as slaves to Spanish America, in the 17th century with West African slaves taken to English colonies in North America.
After the founding of the United States, black people continued to be enslaved, the last four million black slaves were only liberated after the Civil War in 1865. Due to notions of white supremacy, they were treated as second-class citizens; the Naturalization Act of 1790 limited U. S. citizenship to whites only, only white men of property could vote. These circumstances were changed by Reconstruction, development of the black community, participation in the great military conflicts of the United States, the elimination of racial segregation, the civil rights movement which sought political and social freedom. In 2008, Barack Obama became the first African American to be elected President of the United States; the first African slaves arrived via Santo Domingo to the San Miguel de Gualdape colony, founded by Spanish explorer Lucas Vázquez de Ayllón in 1526. The marriage between Luisa de Abrego, a free black domestic servant from Seville and Miguel Rodríguez, a white Segovian conquistador in 1565 in St. Augustine, is the first known and recorded Christian marriage anywhere in what is now the continental United States.
The ill-fated colony was immediately disrupted by a fight over leadership, during which the slaves revolted and fled the colony to seek refuge among local Native Americans. De Ayllón and many of the colonists died shortly afterwards of an epidemic and the colony was abandoned; the settlers and the slaves who had not escaped returned to Haiti, whence. The first recorded Africans in British North America were "20 and odd negroes" who came to Jamestown, Virginia via Cape Comfort in August 1619 as indentured servants; as English settlers died from harsh conditions and more Africans were brought to work as laborers. An indentured servant would work for several years without wages; the status of indentured servants in early Virginia and Maryland was similar to slavery. Servants could be bought, sold, or leased and they could be physically beaten for disobedience or running away. Unlike slaves, they were freed after their term of service expired or was bought out, their children did not inherit their status, on their release from contract they received "a year's provision of corn, double apparel, tools necessary", a small cash payment called "freedom dues".
Africans could raise crops and cattle to purchase their freedom. They raised families, married other Africans and sometimes intermarried with Native Americans or English settlers. By the 1640s and 1650s, several African families owned farms around Jamestown and some became wealthy by colonial standards and purchased indentured servants of their own. In 1640, the Virginia General Court recorded the earliest documentation of lifetime slavery when they sentenced John Punch, a Negro, to lifetime servitude under his master Hugh Gwyn for running away. In the Spanish Florida some Spanish married or had unions with Pensacola, Creek or African women, both slave and free, their descendants created a mixed-race population of mestizos and mulattos; the Spanish encouraged slaves from the southern British colonies to come to Florida as a refuge, promising freedom in exchange for conversion to Catholicism. King Charles II of Spain issued a royal proclamation freeing all slaves who fled to Spanish Florida and accepted conversion and baptism.
Most went to the area around St. Augustine, but escaped slaves reached Pensacola. St. Augustine had mustered an all-black militia unit defending Spain as early as 1683. One of the Dutch African arrivals, Anthony Johnson, would own one of the first black "slaves", John Casor, resulting from the court ruling of a civil case; the popular conception of a race-based slave system did not develop until the 18th century. The Dutch West India Company introduced slavery in 1625 with the importation of eleven black slaves into New Amsterdam. All the colony's slaves, were freed upon its surrender to the British. Massachusetts was the first British colony to recognize slavery in 1641. In 1662, Virginia passed a law that children of enslaved women took the status of the mother, rather than that of the father, as under English common law; this principle was called partus sequitur ventrum. By an act of 1699, the colony ordered all free blacks deported defining as slaves all people of African descent who remained in the c
Texas is the second largest state in the United States by both area and population. Geographically located in the South Central region of the country, Texas shares borders with the U. S. states of Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the west, the Mexican states of Chihuahua, Nuevo León, Tamaulipas to the southwest, while the Gulf of Mexico is to the southeast. Houston is the most populous city in Texas and the fourth largest in the U. S. while San Antonio is the second-most populous in the state and seventh largest in the U. S. Dallas–Fort Worth and Greater Houston are the fourth and fifth largest metropolitan statistical areas in the country, respectively. Other major cities include Austin, the second-most populous state capital in the U. S. and El Paso. Texas is nicknamed "The Lone Star State" to signify its former status as an independent republic, as a reminder of the state's struggle for independence from Mexico; the "Lone Star" can be found on the Texan state seal.
The origin of Texas's name is from the word taysha. Due to its size and geologic features such as the Balcones Fault, Texas contains diverse landscapes common to both the U. S. Southern and Southwestern regions. Although Texas is popularly associated with the U. S. southwestern deserts, less than 10% of Texas's land area is desert. Most of the population centers are in areas of former prairies, grasslands and the coastline. Traveling from east to west, one can observe terrain that ranges from coastal swamps and piney woods, to rolling plains and rugged hills, the desert and mountains of the Big Bend; the term "six flags over Texas" refers to several nations. Spain was the first European country to claim the area of Texas. France held a short-lived colony. Mexico controlled the territory until 1836 when Texas won its independence, becoming an independent Republic. In 1845, Texas joined the union as the 28th state; the state's annexation set off a chain of events that led to the Mexican–American War in 1846.
A slave state before the American Civil War, Texas declared its secession from the U. S. in early 1861, joined the Confederate States of America on March 2nd of the same year. After the Civil War and the restoration of its representation in the federal government, Texas entered a long period of economic stagnation. Four major industries shaped the Texas economy prior to World War II: cattle and bison, cotton and oil. Before and after the U. S. Civil War the cattle industry, which Texas came to dominate, was a major economic driver for the state, thus creating the traditional image of the Texas cowboy. In the 19th century cotton and lumber grew to be major industries as the cattle industry became less lucrative, it was though, the discovery of major petroleum deposits that initiated an economic boom which became the driving force behind the economy for much of the 20th century. With strong investments in universities, Texas developed a diversified economy and high tech industry in the mid-20th century.
As of 2015, it is second on the list of the most Fortune 500 companies with 54. With a growing base of industry, the state leads in many industries, including agriculture, energy and electronics, biomedical sciences. Texas has led the U. S. in state export revenue since 2002, has the second-highest gross state product. If Texas were a sovereign state, it would be the 10th largest economy in the world; the name Texas, based on the Caddo word táyshaʼ "friend", was applied, in the spelling Tejas or Texas, by the Spanish to the Caddo themselves the Hasinai Confederacy, the final -s representing the Spanish plural. The Mission San Francisco de los Tejas was completed near the Hasinai village of Nabedaches in May 1690, in what is now Houston County, East Texas. During Spanish colonial rule, in the 18th century, the area was known as Nuevo Reino de Filipinas "New Kingdom of the Philippines", or as provincia de los Tejas "province of the Tejas" also provincia de Texas, "province of Texas", it was incorporated as provincia de Texas into the Mexican Empire in 1821, declared a republic in 1836.
The Royal Spanish Academy recognizes both spellings and Texas, as Spanish-language forms of the name of the U. S. State of Texas; the English pronunciation with /ks/ is unetymological, based in the value of the letter x in historical Spanish orthography. Alternative etymologies of the name advanced in the late 19th century connected the Spanish teja "rooftile", the plural tejas being used to designate indigenous Pueblo settlements. A 1760s map by Jacques-Nicolas Bellin shows a village named Teijas on Trinity River, close to the site of modern Crockett. Texas is the second-largest U. S. state, with an area of 268,820 square miles. Though 10% larger than France and twice as large as Germany or Japan, it ranks only 27th worldwide amongst country subdivisions by size. If it were an independent country, Texas would be the 40th largest behind Zambia. Texas is in the south central part of the United States of America. Three of its borders are defined by rivers; the Rio Grande forms a natural border with the Mexican states of Chihuahua, Nuevo León, Tamaulipas to the south.
The Red River forms a natural border with Arkansas to the north. The Sabine River forms a natural border with Louisiana to the east; the Texas Panhandle has an eastern border with Oklahoma at 100° W, a northern border with Oklahoma at 36°30' N and a western
Hip hop music
Hip hop music called hip-hop or rap music, is a music genre developed in the United States by inner-city African Americans in the late 1970s which consists of a stylized rhythmic music that accompanies rapping, a rhythmic and rhyming speech, chanted. It developed as part of hip hop culture, a subculture defined by four key stylistic elements: MCing/rapping, DJing/scratching with turntables, break dancing, graffiti writing. Other elements include sampling beats or bass lines from records, rhythmic beatboxing. While used to refer to rapping, "hip hop" more properly denotes the practice of the entire subculture; the term hip hop music is sometimes used synonymously with the term rap music, though rapping is not a required component of hip hop music. Hip hop as both a musical genre and a culture was formed during the 1970s when block parties became popular in New York City among African-American youth residing in the Bronx; however hip-hop music did not get recorded for the radio or television to play until 1979 due to poverty during hip-hop's birth and lack of acceptance outside ghetto neighborhoods.
At block parties DJs played percussive breaks of popular songs using two turntables and a DJ mixer to be able to play breaks from two copies of the same record, alternating from one to the other and extending the "break". Hip hop's early evolution occurred as sampling technology and drum machines became available and affordable. Turntablist techniques such as scratching and beatmatching developed along with the breaks and Jamaican toasting, a chanting vocal style, was used over the beats. Rapping developed as a vocal style in which the artist speaks or chants along rhythmically with an instrumental or synthesized beat. Notable artists at this time include DJ Kool Herc, Grandmaster Flash and The Furious Five, Fab Five Freddy, Marley Marl, Afrika Bambaataa, Kool Moe Dee, Kurtis Blow, Doug E. Fresh, Warp 9, The Fat Boys, Spoonie Gee; the Sugarhill Gang's 1979 song "Rapper's Delight" is regarded to be the first hip hop record to gain widespread popularity in the mainstream. The 1980s marked the diversification of hip hop.
Prior to the 1980s, hip hop music was confined within the United States. However, during the 1980s, it began to spread to music scenes in dozens of countries, many of which mixed hip hop with local styles to create new subgenres. New school hip hop was the second wave of hip hop music, originating in 1983–84 with the early records of Run-D. M. C. and LL Cool J. The Golden age hip hop period was an innovative period between the early 1990s. Notable artists from this era include the Juice Crew, Public Enemy, Eric B. & Rakim, Boogie Down Productions and KRS-One, EPMD, Slick Rick, Beastie Boys, Kool G Rap, Big Daddy Kane, Ultramagnetic MCs, De La Soul, A Tribe Called Quest. Gangsta rap is a subgenre of hip hop that focuses on the violent lifestyles and impoverished conditions of inner-city African-American youth. Schoolly D, N. W. A, Ice-T, Ice Cube, the Geto Boys are key founding artists, known for mixing the political and social commentary of political rap with the criminal elements and crime stories found in gangsta rap.
In the West Coast hip hop style, G-funk dominated mainstream hip hop for several years during the 1990s with artists such as Dr. Dre and Snoop Dogg. East Coast hip hop in the early to mid 1990s was dominated by the Afrocentric jazz rap and alternative hip hop of the Native Tongues posse as well as the hardcore rap of artists such as Mobb Deep, Wu-Tang Clan, Onyx. East Coast hip hop had gangsta rap musicians such as Kool G Rap and the Notorious B. I. G.. In the 1990s, hip hop began to diversify with other regional styles emerging, such as Southern rap and Atlanta hip hop. At the same time, hip hop continued to be assimilated into other genres of popular music, examples being neo soul and nu metal. Hip hop became a best-selling genre in the mid-1990s and the top selling music genre by 1999; the popularity of hip hop music continued through the 2000s, with hip hop influences increasingly finding their way into mainstream pop. The United States saw the success of regional styles such as crunk, a Southern genre that emphasized the beats and music more than the lyrics.
Starting in 2005, sales of hip hop music in the United States began to wane. During the mid-2000s, alternative hip hop secured a place in the mainstream, due in part to the crossover success of artists such as OutKast and Kanye West. During the late 2000s and early 2010s, rappers such as Lil Wayne, Soulja Boy, B.o. B were the most popular rappers. During the 2010s, rappers such as Drake, Nicki Minaj, J. Cole, Kendrick Lamar all have been popular. Trap, a subgenre of hip hop has been popular during the 2010s with hip hop artists and hip hop music groups such as Migos, Travis Scott, Kodak Black; the creation of the term hip hop is credited to Keith Cowboy, rapper with Grandmaster Flash and the Furious Five. However, Lovebug Starski, Keith Cowboy, DJ Hollywood used the term when the music was still known as disco rap, it is believed that Cowboy created the term while teasing a friend who had just joined the U. S. Army, by scat singing the words "hip/hop/hip/hop" in a way that mimicked the rhythmic cadence of soldiers marching.
Cowboy worked the "hip hop" cadence into a part of his stage performance, used by other artists such as The Sugarhi
Philadelphia Police Department
The Philadelphia Police Department is the police agency responsible for law enforcement and investigations within the City of Philadelphia, Pennsylvania. The PPD is one of the oldest municipal police agencies, fourth largest police force and sixth largest non-federal law enforcement agency in the United States. Since records were first kept in 1828, at least 270 PPD officers have died in the line of duty; the PPD employs over 6,400 sworn officers and over 800 civilian personnel, patrols an area of 369.4 km² with a population of 1.5 million. The department is subdivided into 21 patrol districts, like many other large municipal police forces, it incorporates many special units such as a K-9 squad, SWAT, bomb squad, community relations unit, marine unit; the highest-ranking officer is Commissioner Richard Ross. The head of the PPD is the commissioner, appointed by the mayor; the current commissioner is Richard Ross. Under the commissioner are two three-star deputy commissioners; the First Deputy Commissioner heads Field Operations.
The Deputy Commissioner and Chief Administrative Officer heads Organizational Services and Innovation. The Office of Field Operations is headed by the three-star First Deputy Commissioner of Field Operations Myron Patterson; the force comprises two commands, Patrol Operations and, Specialized Operations and Homeland Security. The Specialized Operations and Homeland Security command is headed by a two-star Deputy Commissioner Dennis Wilson, divided into two bureaus, Specialized Investigations and Homeland Security Bureau; the Office of Organizational Services and Innovation is headed by the three-star Deputy Commissioner and Chief Administrative Officer Christine Coulter. Patrol Operations is headed by a two-star Deputy Commissioner of Patrol Operations Joseph Sullivan, who oversees both the patrol and detective units. Patrol Operations is divided into two regional commands, Regional Operations Command and Regional Operations Command; each regional command is headed by a chief inspector, is subdivided into three divisions.
Each division is headed by an inspector. A division comprises four districts; each district is subdivided into three or four police service areas, each headed by a lieutenant, for a total of 64 PSA's citywide. In January 2013, Commissioner Ramsey announced changes to the command structure of the department lowering the number of deputy commissioners from 9 to 6. Ramsey only replaced one of the deputies, promoted from staff inspector of the Internal Affairs Bureau to deputy commissioner of the Office of Professional Responsibility; the beginnings of the mounted unit can be traced to the Fairmount Park Mounted Guard created in 1867. In 1889 the Philadelphia Police Mounted Patrol Unit was established; the Philadelphia Police unit survived until 1952, the Fairmount Park unit would be used for parades and crowd control measures. The Fairmount Park Mounted Guard became the Fairmount Park Police in 1966, but maintained the same responsibilities. In 1972, Mayor Frank Rizzo found it unnecessary for taxpayers to fund two separate police departments, merged the Fairmount Park Police into the Philadelphia Police, creating the Park Division.
The mounted unit was once again used to patrol the streets of Philadelphia. The mounted unit survived to celebrate 100 years in 1989, but was disbanded in 2004 due to budgetary cuts by Mayor John F. Street's administration. On July 18, 2008, Philadelphia Police Commissioner Charles H. Ramsey confirmed that plans are in the works to recreate the mounted unit; the Philadelphia Inquirer again reported on June 2, 2009, that Ramsey hoped to revive the unit once the city was in a better financial standing. The continued recreation of the Mounted Unit took an additional step forward on October 31, 2011, when the city announced plans to build a new facility for the unit in Fairmount Park. To be promoted in the Philadelphia Police Department, a police officer must finish his first year in the department; when the next corporal or detective test is announced, they are eligible to take the test. Philadelphia PD Test for corporal and detectives is a written multiple choice test, lasting two to three hours.
Part of an officer's score is based on seniority. The ranks of corporal and detective have different functions. Corporals are "operations room supervisors" and are responsible for overseeing a patrol district's operations room, or a special unit's operations. Only do corporals work the street. A corporal must have a minimum of a year's experience as a police officer. Sergeants command a squad of officers, making assignments to beats, assigning traffic details, helping to supervise the radio room, commanding Marine Unit patrol boats and performing other similar tasks; when assigned to the detective bureau, a sergeant interviews suspects and witnesses, assigns detectives to cases and investigates clues, among other duties. Sergeants must have a minimum of two years experience as a police officer, or a year's experience as a corporal or detective; the rank of lieutenant is the first executive supervisory rank. Lieutenants command an assigned area in a police district or a specialized unit, such as a traffic unit.
If assigned as a detective, a lieutenant supervises an investigation. Lieu
Basketball is a team sport in which two teams, most of five players each, opposing one another on a rectangular court, compete with the primary objective of shooting a basketball through the defender's hoop while preventing the opposing team from shooting through their own hoop. A field goal is worth two points, unless made from behind the three-point line, when it is worth three. After a foul, timed play stops and the player fouled or designated to shoot a technical foul is given one or more one-point free throws; the team with the most points at the end of the game wins, but if regulation play expires with the score tied, an additional period of play is mandated. Players advance the ball by bouncing it while walking or running or by passing it to a teammate, both of which require considerable skill. On offense, players may use a variety of shots -- a dunk, it is a violation to lift or drag one's pivot foot without dribbling the ball, to carry it, or to hold the ball with both hands resume dribbling.
The five players on each side at a time fall into five playing positions: the tallest player is the center, the tallest and strongest is the power forward, a shorter but more agile big man is the small forward, the shortest players or the best ball handlers are the shooting guard and the point guard, who implements the coach's game plan by managing the execution of offensive and defensive plays. Informally, players may play three-on-three, two-on-two, one-on-one. Invented in 1891 by Canadian-American gym teacher James Naismith in Springfield, United States, basketball has evolved to become one of the world's most popular and viewed sports; the National Basketball Association is the most significant professional basketball league in the world in terms of popularity, salaries and level of competition. Outside North America, the top clubs from national leagues qualify to continental championships such as the Euroleague and FIBA Americas League; the FIBA Basketball World Cup and Men's Olympic Basketball Tournament are the major international events of the sport and attract top national teams from around the world.
Each continent hosts regional competitions for national teams, like FIBA AmeriCup. The FIBA Women's Basketball World Cup and Women's Olympic Basketball Tournament feature top national teams from continental championships; the main North American league is the WNBA, whereas strongest European clubs participate in the EuroLeague Women. In early December 1891, Canadian James Naismith, a physical education professor and instructor at the International Young Men's Christian Association Training School in Springfield, was trying to keep his gym class active on a rainy day, he sought a vigorous indoor game to keep his students occupied and at proper levels of fitness during the long New England winters. After rejecting other ideas as either too rough or poorly suited to walled-in gymnasiums, he wrote the basic rules and nailed a peach basket onto a 10-foot elevated track. In contrast with modern basketball nets, this peach basket retained its bottom, balls had to be retrieved manually after each "basket" or point scored.
Basketball was played with a soccer ball. These round balls from "association football" were made, at the time, with a set of laces to close off the hole needed for inserting the inflatable bladder after the other sewn-together segments of the ball's cover had been flipped outside-in; these laces could dribbling to be unpredictable. A lace-free ball construction method was invented, this change to the game was endorsed by Naismith; the first balls made for basketball were brown, it was only in the late 1950s that Tony Hinkle, searching for a ball that would be more visible to players and spectators alike, introduced the orange ball, now in common use. Dribbling was not part of the original game except for the "bounce pass" to teammates. Passing the ball was the primary means of ball movement. Dribbling was introduced but limited by the asymmetric shape of early balls. Dribbling was common by 1896, with a rule against the double dribble by 1898; the peach baskets were used until 1906 when they were replaced by metal hoops with backboards.
A further change was soon made, so the ball passed through. Whenever a person got the ball in the basket, his team would gain a point. Whichever team got; the baskets were nailed to the mezzanine balcony of the playing court, but this proved impractical when spectators in the balcony began to interfere with shots. The backboard was introduced to prevent this interference. Naismith's handwritten diaries, discovered by his granddaughter in early 2006, indicate that he was nervous about the new game he had invented, which incorporated rules from a children's game called duck on a rock, as many had failed before it. Frank Mahan, one of the players from the original
A college is an educational institution or a constituent part of one. A college may be a degree-awarding tertiary educational institution, a part of a collegiate or federal university, an institution offering vocational education or a secondary school. In the United States, "college" may refer to a constituent part of a university or to a degree-awarding tertiary educational institution, but "college" and "university" are used interchangeably, whereas in the United Kingdom, South Asia, Southern Africa and Canada, "college" may refer to a secondary or high school, a college of further education, a training institution that awards trade qualifications, a higher education provider that does not have university status, or a constituent part of a university. In ancient Rome a collegium was a club or society, a group of people living together under a common set of rules. Aside from the modern educational context - nowadays the most common use of "college" - there are various other meanings derived from the original Latin term, such as Electoral college.
Within higher education, the term can be used to refer to: a constituent part of a collegiate university, for example King's College, Cambridge, or of a federal university, for example King's College London a liberal arts college, an independent institution of higher education focusing on undergraduate education, such as Williams College or Amherst College a liberal arts division of a university whose undergraduate program does not otherwise follow a liberal arts model, such as the Yuanpei College at Peking University an institute providing specialised training, such as a college of further education, for example Belfast Metropolitan College, a teacher training college, or an art college In the United States, college is sometimes but a synonym for a research university, such as Dartmouth College, one of the eight universities in the Ivy League A sixth form college or college of further education is an educational institution in England, Northern Ireland, The Caribbean, Norway, Brunei, or Southern Africa, among others, where students aged 16 to 19 study for advanced school-level qualifications, such as A-levels, BTEC, HND or its equivalent and the International Baccalaureate Diploma, or school-level qualifications such as GCSEs.
In Singapore and India, this is known as a junior college. The municipal government of the city of Paris uses the phrase "sixth form college" as the English name for a lycée. In some national education systems, secondary schools may be called "colleges" or have "college" as part of their title. In Australia the term "college" is applied to any private or independent primary and secondary school as distinct from a state school. Melbourne Grammar School, Cranbrook School and The King's School, Parramatta are considered colleges. There has been a recent trend to rename or create government secondary schools as "colleges". In the state of Victoria, some state high schools are referred to as secondary colleges, although the pre-eminent government secondary school for boys in Melbourne is still named Melbourne High School. In Western Australia, South Australia and the Northern Territory, "college" is used in the name of all state high schools built since the late 1990s, some older ones. In New South Wales, some high schools multi-campus schools resulting from mergers, are known as "secondary colleges".
In Queensland some newer schools which accept primary and high school students are styled state college, but state schools offering only secondary education are called "State High School". In Tasmania and the Australian Capital Territory, "college" refers to the final two years of high school, the institutions which provide this. In this context, "college" is a system independent of the other years of high school. Here, the expression is a shorter version of matriculation college. In a number of Canadian cities, many government-run secondary schools are called "collegiates" or "collegiate institutes", a complicated form of the word "college" which avoids the usual "post-secondary" connotation; this is because these secondary schools have traditionally focused on academic, rather than vocational and ability levels. Some private secondary schools choose to use the word "college" in their names nevertheless; some secondary schools elsewhere in the country ones within the separate school system, may use the word "college" or "collegiate" in their names.
In New Zealand the word "college" refers to a secondary school for ages 13 to 17 and "college" appears as part of the name of private or integrated schools. "Colleges" most appear in the North Island, whereas "high schools" are more common in the South Island. In South Africa, some secondary schools private schools on the English public school model, have "college" in their title, thus no less than six of South Africa's Elite Seven high schools call themselves "college" and fit this description. A typical example of this category would be St John's College. Private schools that specialize in improving children's marks through intensive focus on examination needs are informally called "cram-colleges". In Sri Lanka the word "college" refers to a secondary school, which signifies above the 5th standard. During the British colonial period a limit
Traffic on roads consists of road users including pedestrians, ridden or herded animals, streetcars and other conveyances, either singly or together, while using the public way for purposes of travel. Traffic laws are the laws which govern traffic and regulate vehicles, while rules of the road are both the laws and the informal rules that may have developed over time to facilitate the orderly and timely flow of traffic. Organized traffic has well-established priorities, right-of-way, traffic control at intersections. Traffic is formally organized in many jurisdictions, with marked lanes, intersections, traffic signals, or signs. Traffic is classified by type: heavy motor vehicle, other vehicle, pedestrian. Different classes may be segregated; some jurisdictions may have detailed and complex rules of the road while others rely more on drivers' common sense and willingness to cooperate. Organization produces a better combination of travel safety and efficiency. Events which disrupt the flow and may cause traffic to degenerate into a disorganized mess include road construction and debris in the roadway.
On busy freeways, a minor disruption may persist in a phenomenon known as traffic waves. A complete breakdown of organization may result in traffic gridlock. Simulations of organized traffic involve queuing theory, stochastic processes and equations of mathematical physics applied to traffic flow; the word traffic meant "trade" and comes from the Old Italian verb trafficare and noun traffico. The origin of the Italian words is unclear. Suggestions include Catalan trafegar "decant", an assumed Vulgar Latin verb transfricare'rub across', an assumed Vulgar Latin combination of trans- and facere'make or do', Arabic tafriq'distribution', Arabic taraffaqa, which can mean'seek profit'. Broadly, the term covers many kinds of traffic including network traffic, air traffic, marine traffic and rail traffic, but it is used narrowly to mean only road traffic. Rules of the road and driving etiquette are the general practices and procedures that road users are required to follow; these rules apply to all road users, though they are of special importance to motorists and cyclists.
These rules govern interactions with pedestrians. The basic traffic rules are defined by an international treaty under the authority of the United Nations, the 1968 Vienna Convention on Road Traffic. Not all countries are signatory to the convention and among signatories, local variations in practice may be found. There are unwritten local rules of the road, which are understood by local drivers; as a general rule, drivers are expected to avoid a collision with another vehicle and pedestrians, regardless of whether or not the applicable rules of the road allow them to be where they happen to be. In addition to the rules applicable by default, traffic signs and traffic lights must be obeyed, instructions may be given by a police officer, either or as road traffic control around a construction zone, accident, or other road disruption; these rules should be distinguished from the mechanical procedures required to operate one's vehicle. See driving. Traffic going in opposite directions should be separated in such a way that they do not block each other's way.
The most basic rule is. In many countries, the rules of the road are codified, setting out the legal requirements and punishments for breaking them. In the United Kingdom, the rules are set out in the Highway Code, which includes not only obligations but advice on how to drive sensibly and safely. In the United States, traffic laws are regulated by the states and municipalities through their respective traffic codes. Most of these are based at least in part on the Uniform Vehicle Code, but there are variations from state to state. In states such as Florida, traffic law and criminal law are separate, unless someone flees a scene of an accident, commits vehicular homicide or manslaughter, they are only guilty of a minor traffic offense. However, states such as South Carolina have criminalized their traffic law, so, for example, one is guilty of a misdemeanor for travelling 5 miles over the speed limit. Vehicles come into conflict with other vehicles and pedestrians because their intended courses of travel intersect, thus interfere with each other's routes.
The general principle that establishes who has the right to go first is called "right of way", or "priority". It establishes who has the right to use the conflicting part of the road and who has to wait until the other does so. Signs, signals and other features are used to make priority explicit; some signs, such as the stop sign, are nearly universal. When there are no signs or markings, different rules are observed depending on the location; these default priority rules differ between countries, may vary within countries. Trends toward uniformity are exemplified at an international level by the Vienna Convention on Road Signs and Signals, which prescribes standardized traffic control devices for establishing the right of way where necessary. Crosswalks are common in populated areas, may indicate that pedestrians have priority over vehicular traffic. In most modern cities, the traffic signal is used to establish the right of way on the busy roads, its primary purpose is to give each road a duration of time in which its traffic may use the intersection in an organized way.