all text on fixed permanent signs except route numbers on motorway signs. It is used in two weights: Transport Medium (for light text on dark backgrounds) and Transport Heavy (for dark text on light backgrounds). Motorway has a limited character set consisting of just numbers and a few letters and symbols needed to show route numbers; it has elongated characters and is designed to add emphasis to route numbers on motorways. Motorway is used to sign all route numbers on motorways themselves, and may also be used on non-motorway roads to sign directions in which motorway regulations apply immediately (such as motorway slip roads). Motorway Permanent is light characters on a dark background; Motorway Temporary is dark on light. Transport Medium and Motorway Permanent were developed for the Anderson Committee and appeared on the first motorway signs. The other two typefaces are similar but have additional stroke width in the letters to compensate for light backgrounds. These typefaces are the only ones permitted on road signs in the UK. Although signs containing other typefaces do appear occasionally in some places, they are explicitly forbidden in government guidelines and are technically illegal. Language Bilingual signs are used in Wales. Welsh highway authorities, until 2016, could choose whether the signs in their area were "English-priority" or "Welsh-priority", and the language having priority in each highway authority's area appeared first on signs. Most of south Wales used English-priority while western, mid, and most of northern Wales were Welsh-priority. New regulations that came into force in 2016 mandate all signs to be in Welsh first, with the existing "English-priority" signage being replaced only when they otherwise would. Bilingual signs were permitted by special authorisation after 1965, and in 1972 the Bowen Committee recommended that they should be provided systematically throughout Wales. A small number of multilingual signs exist in the UK on major roads that leave major ports (such as the Port of Dover). They give the UK standard speed limits and remind drivers to drive on the left, in English, French, and German. Multilingual 'no stopping' signs exist in several locations on the M25. In the Scottish Highlands and Islands, many road signs have Scottish Gaelic in green, in addition to English in black. This is part of the Gaelic language revival encouraged by many, including the Scottish Government and Bòrd na Gàidhlig. Retroreflection Road signs in the UK must be retroreflective in