Learning Linux Basics

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Navigating directories and files in Linux is a fundamental skill that allows you to fully exploit the power of the command-line interface (CLI). Mastering essential Linux navigation commands such as cd, pwd, ls, and tree enables you to effortlessly move through the filesystem, display the contents of directories, and understand your location within the system.

Basic Linux Navigation Commands

Here is a brief overview of some of the most common commands used for navigation in Linux:

cd – Change Directory

The cd command allows you to move between directories within the filesystem. It is one of the most frequently used commands when navigating the CLI.

Example:

%%bash
cd /tmp
pwd

This command will move you to the specified directory. If no path is specified, typing cd on its own will take you to your home directory.

  • Absolute Path: /tmp/documents (moves directly to the documents directory within /tmp)

  • Relative Path: ../documents (moves up one directory and into documents)

pwd – Print Working Directory

The pwd command prints the full path of your current directory. This is particularly useful when you’ve navigated through several directories and want to confirm your current location in the filesystem.

Example:

%%bash
mkdir /tmp/documents
cd /tmp/documents
touch file.txt
pwd

ls – List Directory Contents

The ls command lists all files and directories within the current directory. By default, it shows a simple list, but there are many options to customize what is displayed.

Basic usage:

%%bash
cd /tmp/documents
ls

Additional options:

  • ls -l: Displays detailed information about each file, such as permissions, owner, size, and modification date.

  • ls -a: Lists all files, including hidden files (those starting with a dot).

  • ls -lh: Displays sizes in human-readable format (KB, MB, etc.).

ls -l
%%bash
cd /tmp/documents
ls -l
ls -a
%%bash
cd /tmp/documents
ls -a

tree – Display Directory Structure

The tree command visually displays the directory structure as a tree. It’s a useful tool for understanding the layout of files and directories.

Example:

%%bash
cd /tmp/documents
tree ..

This will output a nested tree structure representing the contents of the current directory and its subdirectories.

Practical Examples

Here are some practical examples of how you might use these commands:

  • Navigating to a specific directory:

%%bash
cd /var/log

  • Confirming your location in the filesystem:

%%bash
cd /var/log
pwd

  • Listing files in the current directory in detail:

%%bash
cd /var/log
ls -l

  • Viewing the directory structure:

%%bash
cd /var/log
tree