More than one fifth (22 percent) of grandparents over 60 belong to a social networking site, says MyVoucherCodes.co.uk .

Research by the online vouchers site says of those that belong to a social network, 71 percent used Facebook while 34 percent had signed up to Twitter  and nine percent use LinkedIn.

Furthermore, more than half (51 percent) admitted they joined a social network as they';d been encouraged by younger family members, while 25 percent wanted to find old friends and 20 percent use social networks to keep in touch with friends and family.

Of those asked, 68 per cent said that they had joined their chosen network in the past year, and 51 per cent of those said they had done so because they were encouraged by younger people in their families. A quarter, however, said they wanted to 'find old friends' and a fifth said it was to 'keep in touch with friends and family.'

"I think it's quite a common misconception nowadays that the over- 60s aren't as savvy as others when it comes to the internet. Anyone would love to see their grandparents online, although some grandchildren may want to censor what they say on site with this in mind," said Mark Pearson, chairman of MyVoucherCodes.co.uk.