Terminal & CLI Basics

To the average person, a black screen with white text looks like "hacking." To a developer, the Terminal (also called the Command Line Interface or CLI) is the most powerful tool in the shed.

Instead of clicking through folders with a mouse, you can move, create, and delete files with a few keystrokes. At CodeHarborHub, we use the terminal for everything from running servers to deploying apps.

1. GUI vs. CLI

• GUI (Graphical User Interface): Point, click, and drag. Easy to learn, but slow for repetitive tasks.
• CLI (Command Line Interface): Typing commands. Faster, scriptable, and allows you to control remote servers (like those on AWS).

2. Navigation: Finding Your Way

Think of the terminal as a "You Are Here" map. You are always inside a specific folder (the Working Directory).

Command	Name	What it does
pwd	Print Working Directory	"Where am I right now?"
ls	List	"Show me all files and folders in here."
cd <folder>	Change Directory	"Go inside this folder."
cd ..	Go Back	"Move up one level to the parent folder."

3. File Operations: Building & Cleaning

Now let's learn how to manage your project files without a mouse.

Creating

• mkdir <name>: Make Directory (Create a new folder).
• touch <filename>: Create a new empty file (e.g., touch index.html).

Deleting

• rm <file>: Remove a file.
• rm -rf <folder>: Remove a folder and everything inside it.

Warning

The terminal has no "Recycle Bin." When you delete something here, it is gone forever. Double-check before hitting Enter!

4. Terminal "Superpowers"

Professional developers use these tricks to work at lightning speed:

1. Tab Completion: Start typing a folder name and hit Tab. The terminal will finish the name for you!
2. Up/Down Arrows: Press the Up arrow to see the last command you typed. No need to re-type long commands.
3. clear: Use this when your screen gets too messy and you want a fresh start.
4. Ctrl + C: The "Emergency Stop." If a program is stuck or a server is running, this forces it to stop.

5. The Full-Stack Workflow

Here is a real-world example of how you will use these commands at CodeHarborHub:

# 1. Create a project folder
mkdir my-cool-app

# 2. Go inside it
cd my-cool-app

# 3. Create your main files
touch index.html style.css script.js

# 4. Open it in VS Code immediately
code .

Which Terminal?

• Windows: Use PowerShell or Git Bash.
• Mac/Linux: Use the built-in Terminal (Zsh or Bash).

At CodeHarborHub, we recommend learning Bash/Zsh commands as they are the standard for web servers and cloud environments.