General Linux Commands

cat Dumps a file's contents to stdout.

clear Clears the terminal and leaves you with a clean and fresh prompt at the top. Often in .bash_logout files so that the person who sees your terminal after you cannot see what you were doing just before you logged out. See also: ^l

bg Background a proccess. Good for after you ^z a job.

du Disk Usage. Shows how much space you have used in various folders/devices, depending on how it's used. du -sh folder will show how much space everything is taking up in a folder.

fg Return a process to the foreground. eg after it has been stopped.

reset Resets the terminal. Good for when you mess it up by accidently cating binary data to it.

tail Outputs the last 10 lines of a file. -n 100 will output 100 lines. tail -f file will hold the file open and keep the contents dumping to the screen as the file is added to. Perfect for watching log files.