How far can you go devving on Windows without hitting up Task Manager? Same question and answer on Ubuntu.
In textmode Linux the built-in sort-of equivalent is called up with "top"
Pretty straight forward, shows the current task processes and with hotkeys it allows sorting columns, can be in color, can toggle a combined or multiproc (SMP) overview. It can kill a process with a couple of steps, first you have to hit the "k" key then type in the process id. Not bad for a DOS app. Close it down by pressing the "q" key.
Of course, just like many Windows people prefer SysInternals legendary Process Explorer a lot of Linuxers prefer htop. It's got more colors (hmmmmm, colors), a more graphical info bar for the procs, memory and swap file and, The Biggest Deals, it lets you scroll through the whole list of tasks and if you are remoting in from a moused client you can click on the columns to sort and click on the menu at the bottom to get functions to run.
Ok, it's no Process Explorer (<g>). But for what you've got to work with on a non-gui OS it's a nice tool. Get it with:
sudo aptitude install htop
Coming next: Controlling Ubunut Services, a simple "just do it" and an optional explanation of the wat's going on.