Introduction to the Command Line

Welcome to the first lesson of our command line course! In this lesson, you you will be introduced to the command line interface (CLI) and explain why it's such a powerful and useful tool to understand.

What is the Command Line?

The command line is a text-based interface for interacting with your computer. Instead of using a graphical user interface (GUI) with windows and buttons, you type commands to perform actions. While it might seem intimidating and difficult whto begin, the command line is incredibly powerful and efficient once you get the hang of it. It can also be faster too.

Let's look at a simple example of renaming a file. In a GUI (e.g. Windows), you would need to:

1. Open File Explorer.
2. Navigate to the file.
3. Right-click the file.
4. Select Rename.
5. Type the new name.
6. Press Enter.

The same task in the command line is just one line:

mv oldname.txt newname.txt

This is just one example of how the command line can be quicker and more efficient. As you learn more commands, you'll discover many ways to automate tasks and work more quickly.

Why learn the Command Line?

For developers

• Required for version control such as Git.
• Essential for software development.
• Can be useful for deployment.
• Commonly used for build processes.
• Needed for package management.

For power users

• Faster than graphical interfaces once you learn the required commands.
• More precise control.
• Better automation capabilities.
• Access to advanced features.
• Impcreased productivity and speed.

For system administrators

• Server administration.
• Scheduled tasks.
• Used for remote system management.
• System monitoring.
• Security management.
• Automated maintenance.

Common uses

1. File & folder management
   • Creating, moving, and deleting files,
   • Renaming files.
   • Searching file contents.
   • Batch operations.
2. System administration
   • Monitoring system resources.
   • Installing & updating software.
   • Adding/removing users/roles.
   • Managing services.
3. Development
   • Deploying code.
   • Running development servers.
   • Managing dependencies.
   • Building applications.
   • Running tools such as minification.
4. Automating tasks
   • Creating scripts to reduce manual work.
   • Scheduling tasks.
   • Batch processing.
   • Remove repetition.

Opening the terminal

To begin using the command line you will first need to open a terminal:

• macOS: Open Terminal from Applications > Utilities.
• Windows: Press Windows + R, type cmd and press Enter.
• Linux: Press Ctrl + Alt + T or search for Terminal.

Command line first try

1. Open your terminal
2. Type ls and press Enter.
3. This will list files in the current directory.
4. Try typing date (or time on Windows) to see the current date/time.

Next steps

Coming up, we will explore the different types of terminals and shells available, helping you understand which one is best for your needs.