The number of people using the internet to catch up on their favourite TV shows has almost doubled in the past year.
Watching TV online increased among the British public from 9% of households in 2007 to 17% in 2008, according to a report by the communications regulator Ofcom.
Viewers are increasingly watching programmes when they want and how they want rather than relying on TV schedules, the report suggested.
It is particularly popular among the 15 to 24-year-old age group, with 26% of them using the internet to watch TV in 2008, up 16% in 12 months.
More than half (51%) used it to watch video clips and webcasts.
The report also found that people in the UK spent a record amount of time on the phone last year.
And for the first time young people have become more attached to their mobiles than television.
They watched nearly an hour less TV each week (17 hours) in 2007 than they did in 2002.
Pensioners are increasingly surfing the internet with take-up of computers, mobiles, the internet and digital TV growing at a faster rate among older people than the rest of the population.
The so-called silver surfer, whose interest in such technology has been low until now, is particularly keen on using the internet for email, instant messaging and chat rooms, while a fifth also contribute to someone else’s blog.
Over-65s spend 90 minutes more time online at home each day than their younger counterparts.
For the first time, more money was spent on online advertising spend than the combined advertising spend on ITV1, Channel 4, S4C and Five.