Keiko (1976 - December 12, 2003) was an orca (or killer whale) who stared in the first of three Free Willy movies. Life size animated models were used in all three movies, Keiko never appeared on camera for the final two installments. Wikipedia
The definitive Wikipedia entry for Keiko. Wikipedia is the biggest multilingual free-content encyclopedia on the Internet. en.wikipedia.org/wiki/Keiko_%28orca%29