The chief executive of computer company RM is resigning at the age of 50 to "do something different".

Richard Girling will quit in April after 21 years at the educational computer and software provider, now based at Milton Park, near Abingdon.

Mr Girling has been working full-time since he finished his O-levels at 17.

He said: "When my children went to university it really brought it home to me -- I felt I missed out on that. I think it's time to do different things."

Mr Girling joined RM as a production engineer manager in 1980 when it employed 45 staff in Mill Street, Osney.

It now has 1,400 employees and has a market capitalisation of £257m.

He became chief executive five years ago and said he had been so busy working he had not even had the time to think about what he would do next.

He said: "It had always been my intention to relinquish the chief executive role at around this time.

"While I've no specific plans for the future, I do know I'm ready to do something different."

RM chairman John Leighfield said: "Richard has led RM through a rapid period of growth as a public company.

"He has contributed enormously to our business success and commands immense respect from his peers in the industry."

Tim Pearson, 41, who runs RM's learning division, has taken over Mr Girling's job.