But the library wants to extend this role into the digital world. It recognises the importance of web sites as a great source of historical and cultural material, as well as 'books' that are only published on the net.
The British Library has unveiled its plans for the future. In a consultative document it has detailed a range of proposals, which, if accepted, would see a far greater role for the web and use of digital materials.
Chief Executive Lynne Brindley said this did not mean the end of books. Last year, for example, a record number of books - over 100,000 - were deposited in the British Library.
But the library wants to extend this role into the digital world. It recognises the importance of web sites as a great source of historical and cultural material, as well as 'books' that are only published on the net.
The library has been keeping and cataloguing every volume published in the UK, for over 300 years.
To enable it to make sure such material is not lost forever, the British Library wants to set up collaborative partnerships with other libraries and organisations both in the UK and abroad to archive and catalogue them.
Rich heritage
It also wants to make the most of what it already has and could reach far wider audiences by digitising its vast collection.
Lynne Brindley said she hardly knew where to start because the heritage collections were so rich, containing items like maps, early photographs, music and oral history material.
"These are things in the past that only researchers have been able to have access to," she told BBC News Online. "What we see as very exciting is opening this up over the web so that anybody can get at it, and school children can use it for their assignments."
The issue of greater access is the key to the future of the library and the use of the net has transformed what might be possible. But to implement this strategy, the British Library will have to supplement its funds.
At present it receives £85m a year from the government but it also generates its own income too, about £35m a year. Realistically, one of these figures will have to be significantly boosted to deliver this re-shaping of UK library services.