It is used to launch applications and switch between running applications.
That applies both to accessing the data network and launching applications.
Well, the thing is that the average user doesn't spend his time launching different applications from the Start menu.
To put some of the numbers in perspective, considering launching applications.
The application picker provides an easy way to launch applications.
As a result they often drag things around on their screen when they mean to be launching applications.
But launching applications or doing anything else that requires disk i/o does slow down noticeably.
Appetizer also features a function to automatically launch certain applications when it starts.
System 6's Apple menu cannot be used to launch applications.
The Unity environment doesn't make it easy to launch additional arbitrary applications.