Online Libraries and Archives:
* Internet Archive: [https://archive.org/](https://archive.org/) - A massive digital library with a vast collection of public domain books, including digitized versions of rare and historical texts.
* Project Gutenberg: [https://www.gutenberg.org/](https://www.gutenberg.org/) - A dedicated resource for public domain ebooks with a massive catalog of free downloadable books in various formats.
* Google Books: [https://books.google.com/](https://books.google.com/) - Search within Google Books for books marked as "Public Domain" or "No Copyright."
* HathiTrust: [https://www.hathitrust.org/](https://www.hathitrust.org/) - A collaborative digital library with a vast collection of public domain books, including digitized versions of rare and historical texts.
* Library Genesis (LibGen): [https://libgen.is/](https://libgen.is/) - A controversial but popular source for free academic and public domain books. Use at your own discretion.
Other Resources:
* National Library of Medicine: [https://www.nlm.nih.gov/](https://www.nlm.nih.gov/) - Offers a collection of public domain medical books and historical texts.
* Public Domain Review: [https://publicdomainreview.org/](https://publicdomainreview.org/) - A website dedicated to exploring public domain materials, including books, images, and music.
* Your Local Library: Many libraries have collections of public domain books available for borrowing.
Tips for Finding Public Domain Books:
* Search by author or title: Use online search engines or library catalogs to find specific books.
* Browse by genre or subject: Websites like Project Gutenberg and Internet Archive allow you to browse books by genre or subject.
* Look for copyright information: Most online resources will indicate whether a book is in the public domain.
* Be aware of copyright laws: Even though a book is in the public domain, you may still need to obtain permission to reproduce or distribute it commercially.
Remember, public domain books are free to download, read, and share. Enjoy your literary journey!