Simplify the following text for a Grade 3 native English-speaking person.
Original: Mac OS X Tiger ( version 10.4 ) is the fifth major release of Mac OS X , Apple 's desktop and server operating system for Macintosh computers . Tiger was released to the public on 29 April 2005 for US$ 129.95 as the successor to Mac OS X Panther ( version 10.3 ) , which had been released 18 months earlier .
Simplified: Mac OS X Tiger ( version 10.4 ) is the fifth major release of Apple 's Mac OS X. It was released on April 29 , 2005 .