The top command has been popular with Unix/Linux operating systems for some time. Htop is an different version of the original top command. Htop is not installed by default with some Linux distributions. With Ubuntu, use the following command to install the application.
sudo apt-get install htop
Once installed, simply type “htop” within a terminal prompt.
A series of function key shortcuts are listed at the bottom of the screen. A process can be selected by using the up and down arrows, and then the F9 key can be used to kill it.
The sort order can be modified by using the F6 key.
More information can be found at the project’s main web page at http://htop.sourceforge.net/.