unix

Command line
cd is command directory
ls lists the file in the directory
mkdir creates a directory 
cp copies files from to a directory
mv a file from and to another directory
.. goes back one directory
/ is the root directory
~ is the home directory
pwd shows present working directory
rm -rf remove files or directories 

Unix: a command line interface where you can do some of the normal things like drag and drop, right-click and create folder, copying, and moving files. When computers first started, everything on a computer has to be done in command line, you had to type out what you want to do. Bill Gates (and Steve Jobs) decided that more people understand the computer if there was a simple visual interface where users can interact with. Although it may seems plain, using command line is much faster than manually dragging and dropping files and folders and lets you do much more. You can use Unix to manipulate the data on your computers such as files and folders through commands. Here are some most common commands that you must know to be proficient:
 
Commands:
pwd, ls, mkdir, cd, touch, rm, cp, mv
Options: -r, -rf
Concepts: 
.. vs .
~
sudo
 
A command that might be helpful is: top. It allows you to see what processes are running on your computer.