cd [folder] - changes directory to supplied folder. Other arguments can be "~" (home folder of user running command) and ".." (move up one directory), both these must be entered without the quotes.
man [command] - will display the manual page for any command supplied that offers manual pages. Will offer in-depth explanation of every flag and argument possible with the supplied command.
rm [flags] [directory or filename] - Commonly used to delete files or folders. To delete a non-empty folder the -r (recursive) flag must be supplied.
su [username] - switches user to supplied username. If no username is supplied it will default to root.
sudo [command] - runs the supplied command as super user (sudo = super user do). This will require a password for an admin account, however, it will cache (store) the password for a short time after the first use. This cached password will not be available anywhere but the original terminal shell in which it was first supplied.
locate [term] - is used to locate files that contain the term supplied. Requires "sudo updatedb" to be run to update the locate database.
grep [term] - program that will search supplied input for term supplied (is often used with piped [see below for explanation] input)
cp [flag] [file] [destination] - copies specified file to destination (or directory if the -R (recursive) flag is supplied)
ln -s [original location] [symbolic link] - creates a symbolic link (such as a shortcut in windows) to files, folders, or programs.
echo [content] - used to echo content (enclosed within quotation marks) to the screen, can be diverted to a file using the ">>" characters and then the path to the file, including the file name. (e.g. echo "test123">>Desktop/test123.txt)
cat [filename] - used to output the content of the file to the terminal (again, can be diverted to a file or to the grep command using aforementioned methods).
mkdir [directory name] - Creates a new directory in the current folder, unless a full file path is supplied for the new directory.
pwd - Is a command that prints the working directory (e.g. if you run it in /home/
Programs are usually installed to either /bin/ or /usr/bin, and almost all programs offer manpages, allowing you to use any program you need to just by knowing ls and man. These commands should exist in all *nix environments (mac, linux, unix), however, there may be slight alterations to how they must be entered.
1. A pipe is the character "|" and is used to divert output of a previous command into yet another command (e.g. 'ls|grep "home"')