3: Familiarizing with Terminal and Command Line

Day 2 | Self-study | 2 hours, after work

Today, I am learning the below, before the next LIVE lecture:

- Overview of Terminal

Warning: Below are my study notes as I learn and hence I could be wrong here and there. Please correct me where required and my apologies in advance.

TERMINAL

This is an interface on a computer that allows you to input text and perform various operations. These inputs are often called Command Lines.

In our day-to-day computer use, we are not used to Terminal because we use graphics to operate a computer. Graphics can be loosely described as the "visual treats" you see on your screen. With these, you can create folders & files, rename, move, and delete them, go to different applications, install and uninstall them, etc. Technically speaking, we interact with the company using a GUI.

GUI = Graphical User interface. Sometimes, people pronounce "GUI" as "Goo-ey".

At this stage, I was curious and wanted to learn a bit more about Terminal, Command Line, etc. So, a Google search led me to freeCodeCamp, and I learned the below:

CONSOLE: Tools to interact with the computer (mouse, keyboard, monitor)

TERMINAL: An environment (or a program) on a computer that allows us to input commands or instructions, and the computer returns a result or an output.

Did you know? You can install and uninstall a Terminal, and run many Terminals on a computer.

COMMAND LINE: The space where one enters the commands for the computer to perform specific tasks. Sounds like a Terminal, right? It seems they are the same and the terms can be used interchangeably.

So, now we know there are 2 interfaces for an operating system (OS):

1. CLI
2. GUI

Question: If GUI is easy to use and understand, why even bother with a CLI, especially for a programmer?

Because it's more efficient and quicker, you can automate tasks, and perform repetitive tasks, and in some cases, there's no other way to interact with a computer in a deep technical sort of way.

When you enter a Terminal, you will type your commands after the $ symbol.

I learned some of the common Command Line prompts as well and saw them in action:

~ - a Tilde, represents the home directory

clear - cleans out the Terminal, provides a clean slate

history - shows your previous work (after you've cleaned out a Terminal)

pwd - Print Working Directory, tells you the full path name of the directory you are in

cd - Change Directory, allows you to move into a different directory

mkdir - Make Directory, create a new directory
(mkdir coder - This creates a new folder called, "coder")

ls - List, this command lists the files and folders in the location you are in

touch - Create a new file
(touch manoj.text)

more - Shows the contents in a file
(more manoj.txt)

mv - Move a file or Rename a file
(mv manoj.txt emanoj.text)

. - a single dot represents the current directory

.. - double dots takes you 2 levels above

cp - Copy or duplicate a file
(cp emanoj.text emanoj-copy.text)

rm - Remove - delete a file
(rm emanoj-copy.txt)

man - Manual, if you want a detailed documentation on a specific command
(man rm)

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Phew! That's it for today. It's 9:30 p.m., and I am so tired and sleepy. Time to hit the sack and rejuvenate!