The back button on web browsers is being redesigned to make it easier for surfers to use.

Computer scientists at the University of Canterbury in Christchurch, New Zealand, are looking at ways of making it more efficient.

"The back button is something that everybody uses and pretty much everyone thinks that they know how it behaves," computer scientist Andy Cockburn told the BBC radio programme Go Digital.

"People think it provides access to all of the pages you have been to recently but in fact in only provides access to a subset and very often you click back to find that the page simply isn't there," he added.

Menu redesign

It is obvious that we need to make the user interface as simple as possible Andy Cockburn, computer scientist

The team in New Zealand have been trying out a software program on web browsers that is based on a complete linear history of all the pages visited during a session online.

Both the traditional system and the new linear one have been tested on a selection of volunteers but the results have given no easy answers.

"It is not clear which system browser manufacturers should use," said Mr Cockburn.

This is partly because the new system depends to some degree on the back menu, particularly if users are trying to find pages that they visited many clicks previously.

However not everyone is aware that such a menu exists and it does not always make it clear exactly which pages have been visited.

So now the team are working on making the back menu more efficient with thumbnail representations of the pages visited.

"It is obvious that we need to make the user interface as simple as possible," said Mr Cockburn.