Syntax: nice [Option]... [Command [Arg]...]
Description: The nice command is one of those things that would make the world a better place if everybody used it more often, but nobody does. It allows you to lower the scheduling priority of a process so that less important programs don't get in the way of the important ones.
The nice command is a good example of the power that was lost when graphical interfaces became the default: There is no simple way to adjust the priority of a process with a mouse-driven interface.
Related: nohup, sync, sleep