Activity Monitor

Activity Monitor screenshots

Displays information about all the processes running on your Mac.
Activity Monitor : Activity Monitor

Alternative downloads

AirPort Utility
6.3.1
FREE
Note: Most recent release available only within OS X 10.11 El Capitan update.
Net Monitor
4.9.4
FREE
Net Monitor analyzes the network activity of your computer.
Activity Tracker
1.7.1
FREE
This is a tool which collect the time spent on an application.