What is a primary source?
Check out the OPA Library Skills for website links to Primary Sources online: Primary Resources
Many of these primary sources are being digitized by libraries. Here are some major digital collections:
Here are some interesting documents that have recently been digitized:
The Book of Kells
Recently copyright laws have opened up many resources to the public domain. This year many titles opened up from 1923. The Internet Archive has 11,000 digital books available now:
What are secondary sources?