Basic Terminal Commands
cd directoy_name - change directory, ex: cd Downloads (goes to downloads folder if currently in home folder)
cd .. - change directory, goes back a directory
mkdir directory_name_path - make directory (mkdir hello makes a new folder called hello).
rmdir directory_name_path - removes directory (rmdir hello removes folder hello if it exists).
cat filename - reads a file
ls - lists directories and files in current directory
ls path_to_directory - list all files in specified directories
ls -a - lists all files, even the hidden ones
sudo apt-get install repository - Installs the app or repository