The command line seems formidable at first, but with a few weeks of practice, you may find yourself moving faster and more comfortably than when using graphical applications. Everything you do in a Graphical User Interface (GUI) can be done with a few commands, usually much more efficiently: watching videos, listening to music, sending Tweets, opening files, and of course writing and manipulating code.
Generally speaking, command line tools are standardized and portable (what works on one computer will work on another) in Unix-like environments (Linux, BSD, and Mac OS). The default Windows command line experience is non-standard, but fortunately you can install a Unix-like environment in Windows (see links below).
How to Learn
If you are using Linux, BSD, or Mac OS, you already have everything you need at your disposal. On Mac, open Terminal.app from Spotlight. On Linux and BSD, open your distribution’s terminal application.
If you’re on Windows, you’ll need to install some extra software:
You can also learn online without installing or configuring any extra software here.