Deep in the archives of Australia's National Library, you'll find a copy of every book published since 1968 - a yearly haul that would stretch 2-and-a-half kilometres laid end-to-end.

Now the most precious items of that rich archive are being put on display, not just books but everything from William Shakespeare's first folio of plays to a digitally preserved Wiggles website from the 1990s.

The 'Treasures Gallery' is now open in Canberra.