A variable- message sign abbreviated VMS, CMS, or DMS, in the UK known as a matrix sign, is an electronic traffic sign used on roadways to give travellers information about special events. Such signs warn of traffic congestion, incidents such as terrorist attacks, AMBER/Silver/Blue Alerts, roadwork zones, or speed limits on a specific highway segment. In urban areas, VMS are used within parking guidance and information systems to guide drivers to available car parking spaces, they may ask vehicles to take alternative routes, limit travel speed, warn of duration and location of the incidents, or just inform of the traffic conditions. VMS's were deployed at least as early as the 1950s on the New Jersey Turnpike; the NJ Turnpike's signs of that period, up to around 2012, were capable of displaying a few messages in neon, all oriented around warning drivers to slow down: "REDUCE SPEED", followed by a warning of either construction, congestion, snow, or fog at a certain distance ahead. The New Jersey Turnpike Authority replaced those signs with more flexible electronic signs between 2010 and 2016.
The current VMS systems are deployed on freeways, trunk highways, or in work zones. On the interchange of I-5 and SR 120 in San Joaquin County, California, an automated visibility and speed warning system was installed in 1996 to warn traffic of reduced visibility due to fog, of slow or stopped traffic. Message Signs were deployed in Ontario during the 1990s in the Greater Toronto Area and are now being upgraded on 400 series Highways in the GTA as well as two pilot secondary highways in northeastern Ontario. Early variable message signs included static signs with words that would illuminate indicating the type of incident that occurred, or signs that used rotating prisms to change the message being displayed; these were replaced by dot matrix displays using eggcrate, fiber optic, or flip-disc technology, which were capable of displaying a much wider range of messages than earlier static variable message signs. Since the late 1990s, the most common technology used in new installations for variable message signs are LED displays.
In recent years, some newer LED variable message signs have the ability to display colored text and graphics. Dot-matrix variable message signs are divided into three subgroups: character matrix, row matrix, full matrix. In a character matrix VMS, each character is given its own matrix with equal horizontal spacing between them with two or three rows of characters. In a full matrix VMS, the entire sign is a single large dot matrix display, allowing the display of different fonts and graphics. A row matrix VMS is a hybrid of the two types, divided into two or three rows like a character matrix display, except each row is a single long dot matrix display instead of being split per character horizontally. Overhead variable message signs are today available in three form factors: front access, rear access, walk-in. In a front access variable message sign, maintenance is performed by lifting the sign open from the front. Most smaller VMS are of the front access form factor, are installed today on major arterials.
The rear access form factor is similar to the front access form factor, except that maintenance is performed from the rear of the sign, are used for medium-sized dynamic message signs installed along the roadside of freeways. The walk-in form factor is a more recent introduction, where maintenance on the sign is performed from the inside of the sign. A key advantage of the walk-in form factor is that lane closures are not required to perform maintenance on the sign. Most of the largest VMS units installed today are walk-in units, are installed overhead on freeways; the NJ Turnpike Authority counts five unique types of variable message signs under its jurisdiction, at least one of, replaced by newer signs. They are: "REDUCE SPEED" neon signs. "Changeable message signs". Electronic VMS: signs with remotely controlled messages displayed on them. Variable speed limit signs - used for varying the posted speed limits within work zones and in emergencies. Portable VMS: movable "electronic VMS". A portable VMS has much the same characteristics as a fixed electronic VMS, but can be moved from location to location as the need dictates.
Early models required an operator to be physically present when programming a message, whereas newer models may be reprogrammed remotely via a wired or wireless network or cellphone connection. A complete message on a panel includes a problem statement indicating incident, stalled vehicle etc.. These signs are used for AMBER Alert messages, in some states and Blue Alert messages. In some places, VMSes are set up with permanent, semi-static displays indicating predicted travel times to important traffic destinations such as major cities or interchanges along the route of a highway. Typical messages provide the following information: Promotional messages about services provided by a road authority during non-critical hours, such as carpooling efforts, travelers' information stations a
A mobile phone, cell phone, cellphone, or hand phone, sometimes shortened to mobile, cell or just phone, is a portable telephone that can make and receive calls over a radio frequency link while the user is moving within a telephone service area. The radio frequency link establishes a connection to the switching systems of a mobile phone operator, which provides access to the public switched telephone network. Modern mobile telephone services use a cellular network architecture, therefore, mobile telephones are called cellular telephones or cell phones, in North America. In addition to telephony, 2000s-era mobile phones support a variety of other services, such as text messaging, MMS, Internet access, short-range wireless communications, business applications, video games, digital photography. Mobile phones offering only those capabilities are known as feature phones; the first handheld mobile phone was demonstrated by John F. Mitchell and Martin Cooper of Motorola in 1973, using a handset weighing c. 2 kilograms.
In 1979, Nippon Telegraph and Telephone launched the world's first cellular network in Japan. In 1983, the DynaTAC 8000x was the first commercially available handheld mobile phone. From 1983 to 2014, worldwide mobile phone subscriptions grew to over seven billion—enough to provide one for every person on Earth. In first quarter of 2016, the top smartphone developers worldwide were Samsung and Huawei, smartphone sales represented 78 percent of total mobile phone sales. For feature phones as of 2016, the largest were Samsung and Alcatel. A handheld mobile radio telephone service was envisioned in the early stages of radio engineering. In 1917, Finnish inventor Eric Tigerstedt filed a patent for a "pocket-size folding telephone with a thin carbon microphone". Early predecessors of cellular phones included analog radio communications from trains; the race to create portable telephone devices began after World War II, with developments taking place in many countries. The advances in mobile telephony have been traced in successive "generations", starting with the early zeroth-generation services, such as Bell System's Mobile Telephone Service and its successor, the Improved Mobile Telephone Service.
These 0G systems were not cellular, supported few simultaneous calls, were expensive. The first handheld cellular mobile phone was demonstrated by John F. Mitchell and Martin Cooper of Motorola in 1973, using a handset weighing 2 kilograms; the first commercial automated cellular network analog was launched in Japan by Nippon Telegraph and Telephone in 1979. This was followed in 1981 by the simultaneous launch of the Nordic Mobile Telephone system in Denmark, Finland and Sweden. Several other countries followed in the early to mid-1980s; these first-generation systems could support far more simultaneous calls but still used analog cellular technology. In 1983, the DynaTAC 8000x was the first commercially available handheld mobile phone. In 1991, the second-generation digital cellular technology was launched in Finland by Radiolinja on the GSM standard; this sparked competition in the sector as the new operators challenged the incumbent 1G network operators. Ten years in 2001, the third generation was launched in Japan by NTT DoCoMo on the WCDMA standard.
This was followed by 3.5G, 3G+ or turbo 3G enhancements based on the high-speed packet access family, allowing UMTS networks to have higher data transfer speeds and capacity. By 2009, it had become clear that, at some point, 3G networks would be overwhelmed by the growth of bandwidth-intensive applications, such as streaming media; the industry began looking to data-optimized fourth-generation technologies, with the promise of speed improvements up to ten-fold over existing 3G technologies. The first two commercially available technologies billed as 4G were the WiMAX standard, offered in North America by Sprint, the LTE standard, first offered in Scandinavia by TeliaSonera. 5G is a technology and term used in research papers and projects to denote the next major phase in mobile telecommunication standards beyond the 4G/IMT-Advanced standards. The term 5G is not used in any specification or official document yet made public by telecommunication companies or standardization bodies such as 3GPP, WiMAX Forum or ITU-R.
New standards beyond 4G are being developed by standardization bodies, but they are at this time seen as under the 4G umbrella, not for a new mobile generation. Smartphones have a number of distinguishing features; the International Telecommunication Union measures those with Internet connection, which it calls Active Mobile-Broadband subscriptions. In the developed world, smartphones have now overtaken the usage of earlier mobile systems. However, in the developing world, they account for around 50% of mobile telephony. Feature phone is a term used as a retronym to describe mobile phones which are limited in capabilities in contrast to a modern smartphone. Feature phones provide voice calling and text messaging functionality, in addition to basic multimedia and Internet capabilities, other services offered by the user's wireless service provider. A feature phone has additional functions over and above a basic mobile phone, only capable of voice calling and text messaging. Feature phones and basic mobile phones tend to use a proprietary, custom-designed software and user interface.
By contrast, smartphones use a mobile operating system that shares common traits across devices. There are Orthodox Jewish religious re
Comparison of MUTCD-influenced traffic signs
Road signs used by countries in the Americas are influenced by the Manual on Uniform Traffic Control Devices, first released in 1935, reflecting the influence of the United States throughout the region. Other non-American countries using road signs similar to the MUTCD include Australia, Ireland, Malaysia, New Zealand, Thailand, they are the only countries listed here which drive on the left—with the exception of Liberia and the Philippines, both of which drive on the right. There are a number of American signatories to the Vienna Convention on Road Signs and Signals: Argentina, Chile, Ecuador, French Guiana and Suriname. Of those, only Chile and French Guiana have ratified the treaty. Mandatory action signs in the Americas tend to be influenced by both systems. Nearly all countries in the Americas use yellow diamond warning signs. Recognizing the differences in standards across Europe and the Americas, the Vienna convention considers these types of signs an acceptable alternative to the triangular warning sign.
However, UN compliant signs must make use of more pictograms in contrast to more text based US variants. Indeed, most Pan-American nations make use of more symbols than allowed in the US MUTCD, it is worth noting that, unlike in Europe, considerable variation within road sign designs can exist within nations in multilingual areas. The main differences between traffic signs influenced by the MUTCD relate to: Graphic design and symbological details The use of square-bordered or circular regulatory signs Local languages Most notable is the text on stop signs. Unlike in Europe, the text on stop signs in the Americas varies depending on language, may be multilingual. Below is a table of the main languages used. Note that in non-English speaking countries, English is included on signs near airports and tourist areas. All countries, with the exception of the United States and Great Britain, use the metric system; some countries mark this fact by using units on various signs. Brazil, Ireland, Panama and parts of Canada list units on their maximum speed limit.
In Canada and Ireland, this is a reflection of recent transitions from Imperial to metric. Advisory speed limit signs in most countries list units; the US lists units in mph. Height and width restrictions are always accompanied by units. Signs in some parts of Canada and Mexico near the US border include both metric and Imperial units, to remind American drivers that they are entering metric countries. No such equivalent exists in the US; the US was, at one time. The Metric Conversion Act of 1975 started the process, but it was halted in 1982; the MUTCD specifies metric versions of speed limit signs. Furthermore, Interstate 19 in Arizona is signed in metric. Nearly all MUTCD-influenced warning signs are yellow. There are a few exceptions to this: Pentagonal signs are used in school zones in the United States, Mexico, Malaysia and many areas in Canada. In Japan and the Philippines, pentagonal signs are permanently used for pedestrian crossings. Argentina employs European-style red-bordered triangular warning signs in certain instances where extra attention is required.
The Philippines uses this style for most warning signs, though some highways like the Subic–Clark–Tarlac Expressway and the Manila–Cavite Expressway use MUTCD-style yellow diamond-shaped warning signs. Warning signs may be text-only. Most countries do not use yellow diamond-shaped signs for construction zones. Australia and the Philippines do not use rectangular signs. Prohibitory and restrictive signs are classified as regulatory signs, as per the MUTCD. All prohibitory signs use a red circle with a slash. Restrictive signs use a red circle, as in Europe; some may be seated on a rectangular white background. The original MUTCD prohibitory and restrictive signs were text-only; some of these signs continue to be used in the US. The No Entry / Do Not Enter sign may not feature text. In some Latin American countries, an upwards-pointing arrow contained within a slashed red circle is used instead; some countries have those two signs separated. The Latin American-style'do not proceed straight' sign may take a different meaning in countries with standard No Entry / Do Not Enter signs.
It indicates an intersection where traffic cannot continue straight ahead, but where cross-traffic may enter the street from the right. Thus, it is distinguished from a No Entry /; the design of mandatory signs varies since the MUTCD does not specify their use. Rather, the MUTCD's equivalent are classified as regulatory signs; some countries use simple arrows with its equivalent underneath. This is the MUTCD standard; some countries use European-style white-on-blue circular signs. These are "Type A Mandatory Signs" as prescribed by the Vienna Convention; some Latin American countries use red-bordered circular signs, in the same style as regulatory signs. These are "Type B Mandatory Signs" as prescribed by the Vienna Convention. In cases relating to particular types of vehicle traffic, these signs are identical to some European prohibitory signs. Canada uses a unique sty
Comparison of traffic signs in English-speaking countries
This is a comparison of road signs in countries that speak majorly English, including major ones where it is an official language and understood. Botswana, Lesotho, South Africa, Tanzania and Zimbabwe are all SADC members who drive on the left and use the SADC Road Traffic Signs Manual, thus have identical road signs. All main countries, with except for the United States, the United Kingdom, use the metric system; some countries mark this fact by using units on various signs. Note that some smaller English-speaking countries in the Caribbean use miles per hour. Ireland, parts of Canada list units on their maximum speed limit signs. In Canada and Ireland, this is a reflection of recent transitions from Imperial to metric. Advisory speed limit signs in most countries list units; the US lists units in mph. Height and width restrictions are always accompanied by units. Signs in some parts of Canada near the US border include both metric and Imperial units, to remind American drivers that they are entering metric countries.
No such equivalent exists in the US. The US was, at one time; the Metric Conversion Act of 1975 started the process, but the abolition of the United States Metric Board in 1982 hampered conversion. The MUTCD specifies metric versions of speed limit signs. Furthermore, Interstate 19 in Arizona is signed in metric. Most warning signs are yellow or red-bordered triangular warning signs. There are a few exceptions to this: Pentagonal signs are used in school zones in the United States and many areas in Canada. In the Philippines, pentagonal signs are permanently used for pedestrian crossings. Warning signs may be text-only. Most countries use orange or yellow diamond-shaped signs or yellow, orange or white red-bordered triangular warning signs for construction zones. Australia and the Philippines use rectangular signs. Prohibitory and restrictive signs are classified as regulatory signs. All prohibitory signs use a red circle with a slash. Restrictive signs use a red circle, as in Europe; some may be seated on a rectangular white background.
The original MUTCD prohibitory and restrictive signs were text-only. Some of these signs continue to be used in the US. Yield signs can be blank or have text with the legend "YIELD" or "GIVE WAY" depending on which country it is; the No Entry / Do Not Enter sign may not feature text. In Ireland, an upwards-pointing arrow contained within a slashed red circle is used instead; some countries have those two signs separated. The Latin American-style do not proceed straight sign may take a different meaning in countries with standard No Entry signs, it indicates an intersection where traffic cannot continue straight ahead, but where cross-traffic may enter the street from the right. Thus, it is distinguished from a No Entry sign; the design of mandatory signs varies since the MUTCD does not specify their use. Rather, the MUTCD's equivalent are classified as regulatory signs; some countries use simple arrows with its equivalent underneath. This is Australian standard; some countries use European-style white-on-blue circular signs.
These are "Type A Mandatory Signs" as prescribed by the Vienna Convention. Some Latin American countries use red-bordered circular signs, in the same style as regulatory signs; these are "Type B Mandatory Signs" as prescribed by the Vienna Convention. In cases relating to particular types of vehicle traffic, these signs are identical to some European prohibitory signs. Canada uses a unique style of mandatory sign. Mandatory signs indicating an obligation to turn left do exist, but are not included in the list below since they are functionally mirror versions of signs indicating an obligation to turn right. Comparison of European road signs Comparison of MUTCD-influenced traffic signs Manual on Uniform Traffic Control Devices Traffic sign Vienna Convention on Road Signs and Signals
The M5 is a motorway in England linking the Midlands and the South West. It runs from Junction 8 of the M6 at West Bromwich near Birmingham to Exeter in Devon. Heading south-west, the M5 runs east of West Bromwich and west of Birmingham through Sandwell Valley, it continues past Bromsgrove, Droitwich Spa, Tewkesbury, Gloucester, Weston-super-Mare and Taunton on its way to Exeter, ending at Junction 31. It is the primary gateway to South West England. Congestion is common during the summer holidays, on Friday afternoons, school and bank holidays on the section south of the M4; the M5 follows the route of the A38 road quite closely. The two deviate around Bristol and the area south of Bristol from Junctions 16 to the Sedgemoor services north of Junction 22; the A38 goes straight through the centre of Bristol and passes by Bristol Airport, while the M5 skirts both, with access to the airport from Junctions 18, 19 or 22. The A38 continues south into Devon from the motorway's terminus near Exminster.
Between Junction 21, Weston-super-Mare and Junction 22, Burnham-on-Sea, the M5 passes by an isolated landmark hill called Brent Knoll. The Willow Man sculpture is visible from both carriageways, acts as a landmark just to the south of Junction 23. Junction 15 of the M5 is a large four level stack interchange, called the Almondsbury Interchange, where the M5 meets the busy M4; the Avonmouth Bridge, between Junctions 18 and 19, is a bottleneck during heavy traffic periods, due to lane drops at either ends of the bridge for the respective junctions, the sharp angle in the centre of the bridge, which causes larger vehicles to slow considerably. There are split-level carriageways where the M5 ascends the hill sides above the Gordano Valley, between Portishead, Junction 19 and Clevedon, Junction 20. Junction 1 surrounds a surviving gatehouse from the former Sandwell Hall; the first 26 miles of the M5 motorway to be built were constructed as a dual two-lane motorway, with Worcestershire County Council acting as engineer.
This section, from Junction 4 in the north to a trumpet junction with the M50 in the south, opened in July 1962. The southern end was called a trumpet junction because of its shape: a 270 degree curved bend. There were no other exits from this trumpet junction though room was left for an extension to the south. Worcestershire County Council, the Police and the County Surveyor of Worcestershire made repeated representations that a dual 3-lane standard motorway was appropriate, however the Ministry of Transport insisted that a dual 2-lane motorway would be built at a cost of around £8 million; the Motorways archive records that the carriageways were built to a lower overall width of 88 feet rather than 100 to reduce the loss of agricultural land. When the decision became necessary to widen the Worcestershire section of M5, it cost £123 million; the 2 miles dual two-lane section between Junctions 16 and 17 built at Filton, near Bristol, was opened in 1962, was intended to replace the pre-war Filton bypass.
Gloucestershire County Council acted as engineer for this section, widened to a dual three-lane motorway in 1969. North of Junction 4 the M5 was constructed in sections, from 1967 to 1970, together with the Frankley services. Much of the northern section beyond Junction 3, from about Quinton to the junction with the M6 motorway, was constructed as an elevated dual 3-lane motorway using concrete pillars; the M5 was extended southwards, in sections, from 1967 to 1977, through Gloucestershire & Somerset, to Exeter in Devon as a dual three-lane motorway, together with the Strensham services. The short section between Junctions 27 and 29 was built between 1967 and 1969, by Devon County Council, as the A38 Cullompton Bypass, with the intention that it should become part of the M5; the termini for this section have since been removed, although part of the southern terminal roundabout is now used as an emergency access. The section was developed to motorway standards, incorporated into the M5 in 1975.
The section from Junctions 16 and 18 was illuminated in about 1973 as part or a wider policy announced by UK Minister for Transport Industries in 1972 to illuminate the 86 miles of UK motorway prone to fog. In the late 1980s Junction 4a was built as part of the M42 motorway construction project; the route of the M42 was decided as early as 1972 but, owing to planning delays, the short section of the M42 north of Bromsgrove did not open until 1989. As the M5 traffic increased in the 1980’s Junction 11, the main Gloucester & Cheltenham access became congested. At the same time there were plans for large scale business & housing developments at Brockworth, near Gloucester. To relieve Junction 11 of some of the new traffic generated, & avoid more congestion around both Cheltenham & Gloucester, a new junction, Junction 11A, some 3.5 miles south of Junction 11, was constructed & opened in the mid 1990’s. The first-built section of the M5, from Junctions 4 to 8, was widened to provide six lanes in the early 1990s.
During this work the northbound Strensham services was rebuilt further away from the new junction. Junctions 7 and 8 were remodelled into a roundabout junction; the Avonmouth Bridge was converted to eight lanes in the early 2000s. In 2005–2006, parts of the M5 between Junctions 17 and 20 were widened to 7 lanes.
Direction, position, or indication sign
A direction sign, more defined as a direction, position, or indication sign by the Vienna Convention on Road Signs and Signals, is any road sign used to give information about the location of either the driver or possible destinations, are considered a subset of the informative signs group. Direction signs are far more varied internationally than other classes of sign, as the Vienna Convention does not specify sizes, symbols or positions of such signs. Direction signs are the oldest type of road sign. However, it was not until the invention of the motor car at the turn of the 20th century that modern direction signs evolved, with fewer words and clear design allowing them to be read at speed; the first direction signs were milestones on the Roman road network. As most Roman roads diverged from Rome, one of the numbers was the distance to the Milliarium Aureum, a large golden milestone in the centre of Rome, although sometimes other stones, such as the London Stone, were used in places where measuring distances from Rome was impossible or not useful.
The use of milestones continued following the decline of the Roman Empire. However, as trading between towns and regions increased, milestones were found to be inconvenient for giving directions at crossroads; as a result, the fingerpost developed. Erected by local parishes, fingerposts were cheaper to make. With the development of the turnpike and the stagecoach, the Turnpike Roads Act 1773 was passed, making signposting compulsory to allow the riders to judge their speed and prevent them from becoming lost. Similar signs were developed in other countries and remained in use until the early-20th century, when development of the motor car made the small and wordy signs impractical. Most early direction signs were based on the traditional styles in use in area; these proved unwieldy, modernisation efforts sprang up to change them. However, the changes faced opposition, both from traditionalists who preferred the style or charm of older signs, from businesses along affected routes, which feared that standardised direction signs would favour the new highways, causing rural routes to fade into obscurity.
The advent of World War II halted sign modernisation efforts across Europe and governments removed direction signs from their road networks – fearing that they would assist enemy spies and/or invading forces. The end of the war, on the other hand, presented itself as an opportunity, seized by many European nations, to set about redeveloping their directional signage systems; the construction of high-speed motorways meant that traditional road signs were no longer practical, so new, modern signs with bold, sans serif typefaces and diagrams indicating lanes and sliproads ahead were developed. The British Worboys Committee went further, creating signs with detailed diagrams of junction layouts; such signs have now been in use unchanged for over half a century. The Vienna Convention on Road Signs and Signals divides the direction, position, or indication sign category into direction signs, which are only those giving distances or directions to a given location. Unlike the other classes of sign, direction signs remain broadly undefined by the convention.
Additionally, direction signs on motorways must be blue or green, while temporary direction signs are yellow or orange. As a result, different nations can have wildly different direction signs. Most areas use different colours to show different road types, but the implementation varies: the United Kingdom uses full colour boards, colour-coded to match the type of road they are placed on, with relevant text highlighted within patches of other colours to indicate different road types using the Guildford Rules; the United States and Australia, as well as New Zealand on the other hand universally use the plain green signs, but some signs use different colours to highlight certain types of destination such as hospitals and rest stops, or, in Australia that the road is a tollway. Road signs in Israel and the Palestinian territories are of similar design to North American signage, but vary in color depending on whether the sign indicates direction for through traffic, exiting traffic, etc. Direction signs can be used in conjunction with other types of sign: for example, in the United Kingdom, if a warning or prohibitory sign appears on a direction sign, it means that the route indicated by the sign contains the hazard or prohibition sign posted.
Some areas have special evacuation route signs. The signs point to routes e
Traffic signs or road signs are signs erected at the side of or above roads to give instructions or provide information to road users. The earliest signs were simple wooden or stone milestones. Signs with directional arms were introduced, for example, the fingerposts in the United Kingdom and their wooden counterparts in Saxony. With traffic volumes increasing since the 1930s, many countries have adopted pictorial signs or otherwise simplified and standardized their signs to overcome language barriers, enhance traffic safety; such pictorial signs use symbols in place of words and are based on international protocols. Such signs were first developed in Europe, have been adopted by most countries to varying degrees. Various international conventions have helped to achieve a degree of uniformity in Traffic Signing in various countries. Traffic signs can be grouped into several types. For example, Annexe 1 of the Vienna Convention on Road Signs and Signals, which on 30 June 2004 had 52 signatory countries, defines eight categories of signs: A.
Danger warning signs B. Priority signs C. Prohibitory or restrictive signs D. Mandatory signs E. Special regulation signs F. Information, facilities, or service signs G. Direction, position, or indication signs H. Additional panelsIn the United States, Ireland and New Zealand signs are categorized as follows: Regulatory signs Warning signs Guide signs Street name signs Route marker signs Expressway signs Freeway signs Welcome signs Informational signs Recreation and cultural interest signs Emergency management signs Temporary traffic control signs School signs Railroad and light rail signs Bicycle signsIn the United States, the categories and graphic standards for traffic signs and pavement markings are defined in the Federal Highway Administration's Manual on Uniform Traffic Control Devices as the standard. A rather informal distinction among the directional signs is the one between advance directional signs, interchange directional signs, reassurance signs. Advance directional signs appear at a certain distance from the interchange, giving information for each direction.
A number of countries do not give information for the road ahead, only for the directions left and right. Advance directional signs enable drivers to take precautions for the exit, they do not appear on lesser roads, but are posted on expressways and motorways, as drivers would be missing exits without them. While each nation has its own system, the first approach sign for a motorway exit is placed at least 1,000 metres from the actual interchange. After that sign, one or two additional advance directional signs follow before the actual interchange itself; the earliest road signs were milestones, giving direction. In the Middle Ages, multidirectional signs at intersections became common, giving directions to cities and towns. In 1686, the first known Traffic Regulation Act in Europe is established by King Peter II of Portugal; this act foresees the placement of priority signs in the narrowest streets of Lisbon, stating which traffic should back up to give way. One of these signs still exists in the neighborhood of Alfama.
The first modern road signs erected on a wide scale were designed for riders of high or "ordinary" bicycles in the late 1870s and early 1880s. These machines were fast and their nature made them difficult to control, moreover their riders travelled considerable distances and preferred to tour on unfamiliar roads. For such riders, cycling organizations began to erect signs that warned of potential hazards ahead, rather than giving distance or directions to places, thereby contributing the sign type that defines "modern" traffic signs; the development of automobiles encouraged more complex signage systems using more than just text-based notices. One of the first modern-day road sign systems was devised by the Italian Touring Club in 1895. By 1900, a Congress of the International League of Touring Organizations in Paris was considering proposals for standardization of road signage. In 1903 the British government introduced four "national" signs based on shape, but the basic patterns of most traffic signs were set at the 1908 International Road Congress in Paris.
In 1909, nine European governments agreed on the use of four pictorial symbols, indicating "bump", "curve", "intersection", "grade-level railroad crossing". The intensive work on international road signs that took place between 1926 and 1949 led to the development of the European road sign system. Both Britain and the United States developed their own road signage systems, both of which were adopted or modified by many other nations in their respective spheres of influence; the UK adopted a version of the European road signs in 1964 and, over past decades, North American signage began using some symbols and graphics mixed in with English. Over the years, change was gradual. Pre-industrial signs were stone or wood, but with the development of Darby's method of smelting iron using coke, painted cast iron became favoured in the late 18th and 19th centuries. Cast iron continued to be used until the mid-20th century, but it was displaced by aluminium or other materials and processes, such as vitreous enamelled and/or pressed malleable iron, or steel.
Since 1945 most signs have been made from sheet aluminium with adhesive plastic coatings. Befo