If you're a publisher, you need to give a copy of every UK publication you make to the British Library. Five other major UK libraries may also ask you to give them a copy. This system is called legal deposit and it's been a part of English law since 1662.
Print publications for legal deposit can be books, journals, sheet music, maps, plans, charts or tables. Now legal deposit also covers material published digitally such as websites, blogs, e-journals and CD-ROMs.
Legal deposit has many benefits for publishers and authors. Your deposited publications can be read inside the British Library and will be preserved for future generations. Your works become part of the nation's heritage, providing inspiration for new books and other publications.