The iconic Oyster card started being used on London Buses and the Underground on 30th June 2003. To start with you could only pay as you go, but daily capping was introduced 20 months later on 27th February 2005. London Overground was launched on 11th November 2007 which bought Oyster to the first rail services. The zip card for under 18s concessionary travel was launched on 7th January 2008.
The big bang happened on 2nd January 2010 when Oyster was extended to cover all National Rail services in zones 1-9, plus the Grays area stations just outside. Watford Junction had already been included with London Overground. Only Gatwick Express, Heathrow Express and Southeastern High Speed were excluded.
To mark the occasion, a limited edition of special Oyster cards has been released (see picture). They are available from all zone 1 tube station ticket machines, all visitor centres, and a selection of Oyster ticket stop shops in Central London. I have heard reports that the new stock hasn’t made its way to the front of the queue on some ticket machines, but hopefully that is rare now. The card functions as any normal blue adult Oyster, so can store travelcards and have discounts applied.