Panther vs Leopard

I ordered OS X 10.5 (Leopard) from Amazon.com and it was delivered today. I didn’t buy the boxed retail version of OS X 10.4 (Tiger) because it came installed on my Macintrash, but I did buy the retail version of Panther for my my other Macintrash, a Powerbook. When I opened the box from Amazon, the first thing I noticed was how much smaller Leopard is than Panther.