The Library of Congress offers a wide variety of online databases and Internet resources to the public via the Web, including its own online catalog. In addition, LC provides an easy-to-use gateway for searching other institutions' online catalogs and extensive links to resources on the Internet.
2- Internet History Project
This is a real treasure trove of rare historical documents and books covering a wide range of historical periods and events from the ancient and medieval world to the modern one. Students can browse through its content to find materials relevant to their courses.
3- Art Cyclopedia
When it comes to searching for anything about Art, nothing will top Art Cyclopedia. It provides resources and materials about the world artists, masterpieces, museums, art history and many more.
4- World Digital Library
This is a fantastic library that features resources in different formats and not only the written text, you will find materials in the form of recordings, photos, maps, and videos . You can also conduct searches in it based on the geographical location you select and using the language you want.
5- Project Gutenberg
This is also a great library of ebooks and other searchable data. It includes thousands of free epub and Kindle books that you can either read or download.