Ringworld is a series of science fiction novels written by <a href="/c/books/credit/31585/larry-niven/">Larry Niven</a>, and part of his <a href="/c/books/credit/23209/tales-of-known-space/">Tales of Known Space</a> universe. The first four books in the <a href="/c/books/credit/158181/fleet-of-worlds/">Fleet of Worlds</a> series are a prequel to the Ringworld series; the fifth book Fate of Worlds: Return from the Ringworld is a sequel and serves as a conclusion for both series.
• <a href="/c/books/book/438310/ringworld/">Ringworld</a> (1970)
• <a href="/c/books/book/438356/the-ringworld-engineers/">The Ringworld Engineers</a> (1979)
• <a href="/c/books/book/438358/the-ringworld-throne/">The Ringworld Throne</a> (1996)
• <a href="/c/books/book/438357/ringworlds-children/">Ringworld's Children</a> (2004)
• Fate of Worlds (2012) —this book serves as a conclusion to both the Fleet of Worlds and Ringworld series
Companion book:
• Guide to Larry Niven's Ringworld (1994, with <a href="/c/books/credit/100427/kevin-stein/">Kevin Stein</a>)
https://en.wikipedia.org/wiki/Ringworld_series