10.5, Snow Leopard is 10.6
Mac OS X 10.5 is known as Leopard. The last available version of Leopard was 10.5.8.
The Mac's operating system is called Mac OS X. Each version of Mac OS X is named after a big cat. The current version (number 10.6) is called Snow Leopard; the previous version (10.5) was Leopard and the next version (10.7) will be Lion.
Mac OS X 10.4 was called Tiger and Mac OS X 10.5 was called Leopard. The 10.5 (Leopard) version is better than the 10.4 (Tiger) version. They would not have sold many copies of Leopard if it was worse than Tiger.
Mac OS X 10.5 (Leopard)
I would have to say Mac OS X 10.4 Tiger , Or Leopard
Each version of Apple's operating system for their computers, Mac OS X, is named after a member of the cat family, Tiger, Panther, Leopard etc. The current version, Mac OS X 10.6, is known as Snow Leopard.
All new Macs are supplied with the latest version of Mac OS X which is currently 10.6 Snow Leopard.
To upgrade from Mac OS X 10.4 (Tiger) to 10.5 (Leopard) you will need to buy a boxed version of Mac OS X 10.5. If you have a Mac with an Intel processor you can go straight to Mac OS X 10.6 (Snow Leopard) which is a cheaper upgrade option.
As of December 19, 2010 latest version is Mac OS X Snow Leopard 10.6.5, Build 10H574.
Mac "Lion" and Mac "Snow Leopard" refer to iterations of Apple's Mac OS X (operating system, version 10). "Lion" is the newest as of this writing, and is version 10.7, while "Snow Leopard" is its immediate predecessor, and is version 10.6.
Mac OS X 10.4.11 is the final version of Mac OS X 10.4 (Tiger). To update further will require the purchase of 10.5 (Leopard) or 10.6 (Snow Leopard).
Each version of Apple's Mac OS X is named after a big cat. Mac OS X 10.5 is called "Leopard".