Public address system
Simple PA systems are often used in small venues such as school auditoriums and small bars. Intercom systems, installed in buildings, have both speakers throughout a building, and microphones in many rooms allowing the occupants to respond to announcements. Sound reinforcement systems and PA systems may use some similar components, Sound reinforcement systems are for live music or performance, whereas PA systems are primarily for reproduction of speech. A short time the Automatic Enunciator Company was established in Chicago in order to market the new device, in August 1912 a large outdoor installation was made at a water carnival held in Chicago by the Associated Yacht and Power Boat Clubs of America. Seventy-two loudspeakers were strung in pairs at intervals along the docks. The system was used to announce race reports and descriptions, carry a series of speeches about The Chicago Plan, and provide music between races. Four years later, in 1915, they built a dynamic loudspeaker with a 1-inch voice coil, a 3-inch corrugated diaphragm, the electromagnet created a flux field of approximately 11,000 G.
Their first experiment used a carbon microphone, when the 12 V battery was connected to the system, they experienced one of the first examples of acoustic feedback. They placed the loudspeaker on the roof, and claims say that the amplified human voice could be heard 1 mile away. Jensen and Pridham refined the system and connected a phonograph to the loudspeaker to be able to broadcast recorded music and this demonstration was official presentation of the working system, and approximately 100,000 people gathered to hear Christmas music and speeches with absolute distinctness. The first outside broadcast was one week later, again supervised by Jensen. Jensen oversaw the governor using the microphone while Pridham operated the loudspeaker, the following year and Pridham applied for a patent for what they called their Sound Magnifying Phonograph. Over the next two years developed their first valve amplifier. In 1919 this was standardized as a 3-stage 25 watt amplifier, wilsons speech was part of his nationwide tour to promote the establishment of the League of Nations.
It was held on September 9,1919 at City Stadium, as with the San Francisco installation, Jensen supervised the microphone and Pridham the loudspeakers. Wilson spoke into two large horns mounted on his platform which channelled his voice into the microphone, similar systems were used in the following years by Warren G. Harding and Franklin D. Roosevelt. By the early 1920s, Marconi had established a department dedicated to public address, in 1925, George V used such a system at the British Empire Exhibition, addressing 90,000 via six long-range loudspeakers. This public use of loudspeakers brought attention to the possibilities of such technology, the 1925 Royal Air Force Pageant at Hendon Aerodrome used a Marconi system to allow the announcer to address the crowds, as well as amplify the band
Steam is a digital distribution platform developed by Valve Corporation, which offers digital rights management, multiplayer gaming, video streaming and social networking services. Though initially developed for use on Microsoft Windows operating systems, versions for OS X, mobile apps with connected functionality with the main software were released for iOS, and Windows Phone devices in the 2010s. The Steam platform is considered to be the largest digital platform for PC gaming. By the end of 2015, the service had over 125 million registered accounts, the success of the Steam platform has led to the development of a line of Steam Machine micro-console, as well as SteamOS, a Valve developed fork of the Debian operating system. Valve decided to create a platform that would update automatically and implement stronger anti-piracy. Valve approached several companies, including Microsoft, Yahoo. and RealNetworks to build a client with these features, Steams development began in 2002, with working titles for the platform being Grid and Gazelle.
It was first revealed to the public on March 22,2002, at the Game Developers Conference, to demonstrate the ease of integrating Steam with a game, Relic Entertainment created a special version of Impossible Creatures. However, the game was not released on Steam until 2015, Valve partnered with several companies, including AT&T, and GameSpy Industries. The first mod released on the system was Day of Defeat, the Steam client was first made available for public beta testing in January 2003 during the beta period for Counter-Strike 1.6, for which it was mandatory to install and use. At the time, Steams primary function was streamlining the patch process common in computer games. Steam was a component for all other games. 80, 000–300,000 gamers tested the system when it was in its beta period, the system and website choked under the strain of thousands of users simultaneously attempting to play the latest version of Counter-Strike. In 2004, the World Opponent Network was shut down and replaced by Steam, the online features of games which required World Opponent Network ceased to work unless they were converted to Steam.
Around that time, Valve began negotiating contracts with publishers and independent developers to release their products, including Rag Doll Kung Fu and Darwinia. Canadian publisher Strategy First announced in December 2005 that it would partner with Valve for digital distribution of current, in 2002, the managing director of Valve, Gabe Newell, said he was offering mod teams a game engine license and distribution over Steam for US$995. Valves Half-Life 2 was the first game to require installation of the Steam client to play and this decision was met with concerns about software ownership, software requirements, and issues with overloaded servers demonstrated previously by the Counter-Strike rollout. During this time users faced multiple issues attempting to play the game, although digital distribution could not yet match retail volume, profit margins for Valve and developers were far larger on Steam. Large developer-publishers, including id Software, Eidos Interactive, and Capcom, by May that year,13 million accounts had been created on the service, and 150 games were for sale on the platform
David Keith Lynch is an American director, producer, painter and photographer. He has been described by The Guardian as the most important director of this era, allMovie called him the Renaissance man of modern American filmmaking, while the success of his films has led to him being labelled the first popular Surrealist. He moved to Los Angeles, where he produced his first motion picture, Lynch embraced the Internet as a medium, producing several web-based shows, such as the animated DumbLand and the surreal sitcom Rabbits. Lynch has received three Academy Award nominations for Best Director and a nomination for best screenplay. He has won Frances César Award for Best Foreign Film twice, as well as the Palme dOr at the Cannes Film Festival, the French government awarded him the Legion of Honor, the countrys top civilian honor, as a Chevalier in 2002 and an Officier in 2007. Blue Velvet and Mulholland Drive are widely considered by critics to be among the greatest films of their respective decades, Lynch was born in Missoula, Montana on January 20,1946.
His father, Donald Walton Lynch, was a research scientist working for the U. S. Department of Agriculture, Lynchs maternal great-grandparents were Finnish, and had immigrated to the United States from Finland in the 19th century. The Lynch family often moved around according to where the USDA assigned Donald and it was here that Lynchs sister Martha was born. The family moved to Durham, North Carolina, Idaho, Lynch found this transitory early life relatively easy to adjust to, noting that he found it fairly easy to meet new friends whenever he started attending a new school. Commenting on much of his life, Lynch has remarked, Alongside his schooling, Lynch joined the Boy Scouts, although he would note that he only became so I could quit. He rose to the highest rank of Eagle Scout and it was through being an Eagle Scout that he was present with other Boy Scouts outside of the White House at the inauguration of President John F. Kennedy, which took place on Lynchs birthday in 1961. They had some hopes that in Europe they could train with the expressionist painter Oskar Kokoschka at his school.
Upon reaching Salzburg, they found that he was not available and, Back in the United States, Lynch returned to Virginia, but since his parents had moved to Walnut Creek, California, he stayed with his friend Toby Keeler for a while. He decided to move to the city of Philadelphia and enroll at the Pennsylvania Academy of Fine Arts, after advice from Jack Fisk and it was here that he began a relationship with a fellow student, Peggy Reavey, and they were married in 1967. The following year, Peggy gave birth to their daughter Jennifer, describing this situation, Peggy stated that definitely was a reluctant father, but a very loving one. Hey, I was pregnant when we got married, describing living there, Lynch stated that We lived cheap, but the city was full of fear. A kid was shot to death down the street and we were robbed twice, had windows shot out and a car stolen. The house was first broken into three days after we moved in
Humble Bundle continues to offer these limited-time bundles, but have expanded to include a persistent storefront. Initial bundles were typically collections of independently developed games featuring multi-platform support provided without digital rights management, occurring every few months, the two-week Humble Bundles drew media attention, with several bundles surpassing $1 million in sales. Bundles are presently offered on a regular basis, with a persistent storefront for individual game sales. The Humble Bundle offerings support a number of charities, including Childs Play, the Electronic Frontier Foundation, water, the American Red Cross, by October 2015, the total charitable amount raised by the Bundles exceeded $65 million across 50 different charities. By the end of October 2014, participating developers have grossed more than $100 million, the success of the Humble Bundle approach has inspired a number of similar efforts to offer pay what you want bundles for smaller titles, including Indie Gala and Indie Royale.
As a corporation, Humble Bundle is headquartered in San Francisco, the idea for the Bundle was from Jeff Rosen of Wolfire Games. Rosen describes the coming to him through similar sales of bundle packages on the Steam platform. Rosen had noted that sales would have viral word-of-mouth spread across the Internet. Wolfire had teamed with Unknown Worlds Entertainment to offer a bundle based on their Natural Selection 2 game. The porter of Lugaru to Linux was Ryan C, who was responsible for porting Aquaria to Linux. The site added the option to pay via Bitcoin only through Coinbase, Rosen sought to include charities in the bundle, allowing the purchaser to choose how to distribute the funds between the developers and charities. The means of pay-what-you-want would allow purchasers to simply give the money to the charities and Wolfire employee John Graham provided technical support during the sales, handling thousands of requests through a few all-night email and chat sessions. In April 2011, it was announced that Sequoia Capital had invested $4.7 million of capital into Humble Bundle.
The full arrangements with developers to create the bundle typically conclude a month before the bundle goes live, the Humble Bundle group earns about 15% of the total funds raised. The Humble Store is an extension of the system developed for managing the Humble Bundles. It offers the capabilities of the payment and customer services that they had created for the various Bundles to independent developers as a marketplace for these titles. Once developers have signed on with the Humble Store, they are given a widget that they can include on their web site allows users to purchase the game. In some cases, such as with FTL, Faster Than Light and Sportsfriends, as with the Bundles, once purchased the buyer has access to all software titles from the store at any time
A map is a symbolic depiction emphasizing relationships between elements of some space, such as objects, regions, or themes. Many maps are static, fixed to paper or some other durable medium, although the earliest maps known are of the heavens, geographic maps of territory have a very long tradition and exist from ancient times. The word map comes from the medieval Latin Mappa mundi, wherein mappa meant napkin or cloth, map became the shortened term referring to a two-dimensional representation of the surface of the world. Cartography or map-making is the study and practice of crafting representations of the Earth upon a flat surface, in addition to location information maps may be used to portray contour lines indicating constant values of elevation, rainfall, etc. The orientation of a map is the relationship between the directions on the map and the compass directions in reality. The word orient is derived from Latin oriens, meaning East, in the Middle Ages many maps, including the T and O maps, were drawn with East at the top.
Today, the most common – but far from universal – cartographic convention is that North is at the top of a map, several kinds of maps are often traditionally not oriented with North at the top, Maps from non-Western traditions are oriented a variety of ways. Old maps of Edo show the Japanese imperial palace as the top, labels on the map are oriented in such a way that you cannot read them properly unless you put the imperial palace above your head. Medieval European T and O maps such as the Hereford Mappa Mundi were centred on Jerusalem with East at the top, prior to the reintroduction of Ptolemys Geography to Europe around 1400, there was no single convention in the West. Portolan charts, for example, are oriented to the shores they describe, Maps of cities bordering a sea are often conventionally oriented with the sea at the top. Route and channel maps have traditionally been oriented to the road or waterway they describe, polar maps of the Arctic or Antarctic regions are conventionally centred on the pole, the direction North would be towards or away from the centre of the map, respectively.
Typical maps of the Arctic have 0° meridian towards the bottom of the page, reversed maps, known as Upside-Down maps or South-Up maps, reverse the North is up convention and have south at the top. Buckminster Fullers Dymaxion maps are based on a projection of the Earths sphere onto an icosahedron, the resulting triangular pieces may be arranged in any order or orientation. Modern digital GIS maps such as ArcMap typically project north at the top of the map, compass decimal degrees can be converted to math degrees by subtracting them from 450, if the answer is greater than 360, subtract 360. The scale statement may be taken as exact when the region mapped is small enough for the curvature of the Earth to be neglected, over larger regions where the curvature cannot be ignored we must use map projections from the curved surface of the Earth to the plane. Thus for map projections we must introduce the concept of point scale, which is a function of position, although the scale statement is nominal it is usually accurate enough for all but the most precise of measurements.
Large scale maps, say 1,10,000, cover relatively small regions in detail and small scale maps, say 1,10,000,000, cover large regions such as nations, continents. The large/small terminology arose from the practice of writing scales as numerical fractions, there is no exact dividing line between large and small but 1/100,000 might well be considered as a medium scale
Eurogamer is a website and YouTube channel focused on video game news and other features. It is operated by Gamer Network Ltd. with headquarters in Brighton, East Sussex, the site primarily caters to a UK/Ireland audience, Gamer Network operates other sites using the Eurogamer brand that caters to other European countries. Most of its reviews are of European or PAL releases of the games, eurogamers current editor is Oli Welsh, who took over the role from Tom Bramwell in September 2014. The editor prior to Bramwell was Kristan Reed. biz editor Rob Fahey, Eurogamer founder Rupert Loman was interviewed in February 2007 by MCV magazine. He was featured in the Sunday Telegraph on 19 August 2007, at the Games Media Awards, Eurogamer won the categories of Best Games Website – News, and Best Games Website – Reviews & Features in 2007. Deputy Editor Tom Bramwell won Best Writer in Specialist Digital Media, News editor Wesley Yin-Poole won Best News Writer in 2014. Rupert Loman was winner of Entrepreneur of the Year 2003 at the Sussex Business Awards and he was selected as one of 30 Young Guns by Growing Business magazine in October 2008.
At the Leipzig Games Convention in August 2006, Eurogamer launched their first non-English language site of the franchise, in April 2011, Eurogamer Netherlands and Eurogamer Belgium merged to form Eurogamer Benelux. Eurogamer Romania closed down in 2011, in November 2012, Eurogamer launched their first non-European site, and 2012–2013 saw the launch of USgamer, Gamer Networks US flagship multi-format games website. Eurogamer has a site, GamesIndustry. biz, which reports on the global video games industry. In May 2008 the site launched the GamesIndustry. biz Network for industry professionals, Eurogamer has hosted the Digital Foundry channel since 2007. Digital Foundry evaluates video game hardware and software from a technical level, often comparing performances of the same game across different platforms
Kentucky, officially the Commonwealth of Kentucky, is a state located in the east south-central region of the United States. Kentucky is one of four U. S. states constituted as a commonwealth, originally a part of Virginia, in 1792 Kentucky became the 15th state to join the Union. Kentucky is the 37th most extensive and the 26th most populous of the 50 United States, Kentucky is known as the Bluegrass State, a nickname based on the bluegrass found in many of its pastures due to the fertile soil. One of the regions in Kentucky is the Bluegrass Region in central Kentucky. In 1776, the counties of Virginia beyond the Appalachian Mountains became known as Kentucky County, the precise etymology of the name is uncertain, but likely based on an Iroquoian name meaning the meadow or the prairie. Kentucky is situated in the Upland South, a significant portion of eastern Kentucky is part of Appalachia. Kentucky borders seven states, from the Midwest and the Southeast, West Virginia lies to the east, Virginia to the southeast, Tennessee to the south, Missouri to the west and Indiana to the northwest, and Ohio to the north and northeast.
Only Missouri and Tennessee, both of which border eight states, touch more, Kentuckys northern border is formed by the Ohio River and its western border by the Mississippi River. The official state borders are based on the courses of the rivers as they existed when Kentucky became a state in 1792, for instance, northbound travelers on U. S.41 from Henderson, after crossing the Ohio River, will be in Kentucky for about two miles. Ellis Park, a racetrack, is located in this small piece of Kentucky. Waterworks Road is part of the land border between Indiana and Kentucky. Kentucky has a part known as Kentucky Bend, at the far west corner of the state. It exists as an exclave surrounded completely by Missouri and Tennessee, Road access to this small part of Kentucky on the Mississippi River requires a trip through Tennessee. The epicenter of the powerful 1811–12 New Madrid earthquakes was near this area, much of the outer Bluegrass is in the Eden Shale Hills area, made up of short and very narrow hills.
The Jackson Purchase and western Pennyrile are home to several bald cypress/tupelo swamps, located within the southeastern interior portion of North America, Kentucky has a climate that can best be described as a humid subtropical climate. Temperatures in Kentucky usually range from daytime summer highs of 87 °F to the low of 23 °F. The average precipitation is 46 inches a year, Kentucky experiences four distinct seasons, with substantial variations in the severity of summer and winter. The highest recorded temperature was 114 °F at Greensburg on July 28,1930 while the lowest recorded temperature was −37 °F at Shelbyville on January 19,1994, due to its location, Kentucky has a moderate humid subtropical climate, with abundant rainfall
Mammoth Cave National Park
Mammoth Cave National Park is a U. S. national park in central Kentucky, encompassing portions of Mammoth Cave, the longest cave system known in the world. Since the 1972 unification of Mammoth Cave with the system under Flint Ridge to the north. The park was established as a park on July 1,1941. It became a World Heritage Site on October 27,1981, the parks 52,830 acres are located primarily in Edmonson County, with small areas extending eastward into Hart County and Barren County. It is centered on the Green River, with a tributary, with 405 miles of surveyed passageways Mammoth Cave is by far the worlds longest known cave system, being over twice as long as the second-longest cave system, Mexicos Sac Actun underwater cave. Mammoth Cave developed in thick Mississippian-aged limestone strata capped by a layer of sandstone and it is known to include more than 390 miles of passageway, new discoveries and connections add several miles to this figure each year. Mammoth Cave National Park was established to preserve the cave system, the epikarstic zone concentrates local flows of runoff into high-elevation springs which emerge at the edges of ridges.
It is in underlying massive limestone layers that the human-explorable caves of the region have naturally developed. The limestone layers of the column beneath the Big Clifty, in increasing order of depth below the ridgetops, are the Girkin Formation. Genevieve Limestone, and the St. Louis Limestone, for example, the large Main Cave passage seen on the Historic Tour is located at the bottom of the Girkin and the top of the Ste. Each of the layers of limestone is divided further into named geological units and subunits. One area of research involves correlating the stratigraphy with the cave survey produced by explorers. This makes it possible to produce approximate three-dimensional maps of the contours of the layer boundaries without the necessity for test wells. The upper sandstone caprock is relatively hard for water to penetrate, the sandstone caprock layer has been dissolved and eroded at many locations within the park, such as the Frozen Niagara room. At one valley bottom in the region of the park.
Known as Cedar Sink, the features a small river entering one side. Mammoth Cave is home to the endangered Kentucky cave shrimp, a sightless albino shrimp, the National Park Service offers several cave tours to visitors. Some notable features of the cave, such as Grand Avenue, Frozen Niagara, two tours, lit only by visitor-carried paraffin lamps, are popular alternatives to the electric-lit routes
A truck driver is a person who earns a living as the driver of a truck. Truck drivers are responsible for inspecting all their vehicles for mechanical items or issues relating to safe operation. Others, such as workers, are responsible for sales. There are ones that lease a truck from a company, company drivers are employees of a particular trucking company and drive trucks provided by their employer. Both owner operators/owner driver and company drivers can be in these categories, auto haulers work hauling cars on specially built trailers and require specific skills loading and operating this type of specialized trailer. Boat haulers work moving boats ranging in size from 10-foot-long bass boats to full-size yachts up to 60 ft long using a low boy trailer that can be set up for each size of boat. Boats wider than 8 feet 6 inches wide or 13 feet 6 inches high have to have a permit to move and are an oversize load, dry van drivers haul the majority of goods over highways in large trailers. Contents may be perishable or non perishable goods, dry bulk pneumatic drivers haul bulk sand and cement, among other things.
They have specialized trailers that allow them to use pressurized air to unload their product, - Commonly known as Flow Boys among truckers. Flat bed drivers haul an assortment of large bulky items, a few examples are tanks, steel pipes and lumber. Drivers require the ability to balance the load correctly, reefer drivers haul refrigerated, temperature sensitive or frozen goods. Local drivers work only within the limits of their local areas and these areas may include crossing state lines, but drivers usually return home daily. Household goods drivers, or bedbuggers, haul personal effects for families who are moving from one home to another, Regional drivers may work over several states near their homes. They may be away from home for short periods, Interstate drivers often cover distances of thousands of miles and are away from home for days, weeks or even months on end. For time critical loads, companies may opt to employ team drivers which can cover more miles than a single driver. Team drivers are two drivers who take turns driving the truck in shifts, or several people in different states that split up the haul to keep from being away from home for such long periods.
Tanker drivers haul liquids, such as gasoline, diesel fuel, milk, & crude oil, liquid tanker drivers need special driving skills due to the load balance changing from the liquid movement. This is especially true for food grade tankers, which do not contain any baffles and are a single compartment, fuel oil/petroleum drivers require special certifications
Within the market of desktop and home computers, and by web usage, it is the second most widely used desktop OS after Microsoft Windows. Launched in 2001 as Mac OS X, the series is the latest in the family of Macintosh operating systems, Mac OS X succeeded classic Mac OS, which was introduced in 1984, and the final release of which was Mac OS9 in 1999. An initial, early version of the system, Mac OS X Server 1.0, was released in 1999, the first desktop version, Mac OS X10.0, followed in March 2001. In 2012, Apple rebranded Mac OS X to OS X. Releases were code named after big cats from the release up until OS X10.8 Mountain Lion. Beginning in 2013 with OS X10.9 Mavericks, releases have been named after landmarks in California, in 2016, Apple rebranded OS X to macOS, adopting the nomenclature that it uses for their other operating systems, iOS, watchOS, and tvOS. The latest version of macOS is macOS10.12 Sierra, macOS is based on technologies developed at NeXT between 1985 and 1997, when Apple acquired the company.
The X in Mac OS X and OS X is pronounced ten, macOS shares its Unix-based core, named Darwin, and many of its frameworks with iOS, tvOS and watchOS. A heavily modified version of Mac OS X10.4 Tiger was used for the first-generation Apple TV, Apple used to have a separate line of releases of Mac OS X designed for servers. Beginning with Mac OS X10.7 Lion, the functions were made available as a separate package on the Mac App Store. Releases of Mac OS X from 1999 to 2005 can run only on the PowerPC-based Macs from the time period, Mac OS X10.5 Leopard was released as a Universal binary, meaning the installer disc supported both Intel and PowerPC processors. In 2009, Apple released Mac OS X10.6 Snow Leopard, in 2011, Apple released Mac OS X10.7 Lion, which no longer supported 32-bit Intel processors and did not include Rosetta. All versions of the system released since run exclusively on 64-bit Intel CPUs, the heritage of what would become macOS had originated at NeXT, a company founded by Steve Jobs following his departure from Apple in 1985.
There, the Unix-like NeXTSTEP operating system was developed, and launched in 1989 and its graphical user interface was built on top of an object-oriented GUI toolkit using the Objective-C programming language. This led Apple to purchase NeXT in 1996, allowing NeXTSTEP, called OPENSTEP, previous Macintosh operating systems were named using Arabic numerals, e. g. Mac OS8 and Mac OS9. The letter X in Mac OS Xs name refers to the number 10 and it is therefore correctly pronounced ten /ˈtɛn/ in this context. However, a common mispronunciation is X /ˈɛks/, consumer releases of Mac OS X included more backward compatibility. Mac OS applications could be rewritten to run natively via the Carbon API, the consumer version of Mac OS X was launched in 2001 with Mac OS X10.0. Reviews were variable, with praise for its sophisticated, glossy Aqua interface
Eagle is a common name for many large birds of prey of the family Accipitridae, it belongs to several groups of genera that are not necessarily closely related to each other. Most of the 60 species of eagles are from Eurasia and Africa, outside this area, just 14 species can be found – two in North America, nine in Central and South America, and three in Australia. Eagles are large, powerfully built birds of prey, with heavy heads, most eagles are larger than any other raptors apart from some vultures. The smallest species of eagle is the South Nicobar serpent eagle, the largest species are discussed below. Like all birds of prey, eagles have large, hooked beaks for ripping flesh from their prey, muscular legs. The beak is typically heavier than that of most other birds of prey, Eagles eyes are extremely powerful, having up to 3.6 times human acuity for the martial eagle, which enables them to spot potential prey from a very long distance. This keen eyesight is primarily attributed to their extremely large pupils which ensure minimal diffraction of the incoming light, the female of all known species of eagles is larger than the male.
Eagles normally build their nests, called eyries, in trees or on high cliffs. Many species lay two eggs, but the older, larger chick frequently kills its younger sibling once it has hatched, the dominant chick tends to be a female, as they are bigger than the male. The parents take no action to stop the killing, due to the size and power of many eagle species, they are ranked at the top of the food chain as apex predators in the avian world. The type of prey varies by genus, the snake and serpent eagles of the genera Circaetus and Spilornis predominantly prey on the great diversity of snakes found in the tropics of Africa and Asia. The eagles of the genus Aquila are often the top birds of prey in open habitats, where Aquila eagles are absent, other eagles, such as the buteonine black-chested buzzard-eagle of South America, may assume the position of top raptorial predator in open areas. Many other eagles, including the species-rich Spizaetus genus, live predominantly in woodlands and these eagles often target various arboreal or ground-dwelling mammals and birds, which are often unsuspectingly ambushed in such dense, knotty environments.
Hunting techniques differ among the species and genera, with some individual eagles having engaged in quite varied techniques based their environment, most eagles grab prey without landing and take flight with it, so the prey can be carried to a perch and torn apart. The bald eagle is noted for having flown with the heaviest load verified to be carried by any flying bird and crowned eagles have killed ungulates weighing up to 30 kg and a martial eagle even killed a 37 kg duiker, 7–8 times heavier than the preying eagle. It has been observed that most birds of prey look back over their shoulders before striking prey, all hawks seem to have this habit, from the smallest kestrel to the largest Ferruginous – but not the Eagles. Among the eagles are some of the largest birds of prey, only the condors and it is regularly debated which should be considered the largest species of eagle. They could be measured variously in total length, body mass, different lifestyle needs among various eagles result in variable measurements from species to species