Format
The format of the contest has changed over the years, though the basic tenets have always been thus: participant countries submit songs, which are performed live in a television programme transmitted across the Eurovision Network by the EBU simultaneously to all countries. A "country" as a participant is represented by one television broadcaster from that country: typically, but not always, that country's national public broadcasting organisation. The programme is hosted by one of the participant countries, and the transmission is sent from the auditorium in the host city. During this programme, after all the songs have been performed, the countries then proceed to cast votes for the other countries' songs: nations are not allowed to vote for their own song. At the end of the programme, the winner is declared as the song with the most points. The winner receives, simply, the prestige of having won—although it is usual for a trophy to be awarded to the winning songwriters, and the winning country is invited to host the event the following year.
The programme is invariably opened by one or more presenters, welcoming viewers to the show. Most host countries choose to capitalise on the opportunity afforded them by hosting a programme with such a wide-ranging international audience, and it is common to see the presentation interspersed with video footage of scenes from the host nation, as if advertising for tourism. Between the songs and the announcement of the voting, an interval act is performed. These acts can be any form of entertainment imaginable. Interval entertainment has included such acts as The Wombles (1974) and the first international presentation of Riverdance (1994).
As national broadcasters join and leave the EBU feed, the EBU/Eurovision logo is displayed. The accompanying theme music (used on other Eurovision broadcasts) is the prelude to Marc-Antoine Charpentier's Te Deum.
The Eurovision Song Contest final is traditionally held on a spring Saturday evening, at 19:00 UTC (20:00 BST/IST, or 21:00 CEST). Usually one Saturday in May is chosen, although the contest has been held on a Thursday (in 1956) and as early as March.
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