One thing that Mac OS X finally introduces to the Macintosh is something that many users have wanted for years: Pre-emptive multitasking (and a real Minimize command), and memory protection. This is all a direct result of using UNIX as a backend rather than their own core.

The minimizing of applications is something that has never existed on the Mac until now, and it is implemented in the dock. When you minimize a program, it does a very fancy sort of drain-like animation and appears as a thumbnail in the dock. The animation can be customized as well.
Compare this to Windows of the time. Windows XP of a year later didn't even have window previews!

Some new changes to the Finder:

• There are links in the form of buttons at the top, leading to common places such as the Applications folder.
• There is now a back button, as well as a navigation thing.
• The top bar still says Desktop rather than Finder.
• Icon view shows slightly larger icons than before.
• There is a new Column view that wasn't present before.
• New folders open up in the same window, rather than a different one.

Also notice the window controls. By default they are just colored buttons, and if the window doesn't have focus they fade to having no color like the rest of the title bar. Mousing over them reveals the symbols. This is done to save space and reduce clutter.

By default, like previous versions, Mac OS X uses the fail of a web browser known as Internet Explorer to do web browsing. Thank god for browsers like Classilla!

Most of the old OS 9 applications have been given a facelift but have been otherwise unchanged.

The control panel doesn't use any kind of hierarchy yet, and there is a Pane menu containing all the control panel applets that isn't present in later versions.