Using the Linux Bash Terminal

Learn how to navigate, manage, and automate with Bash

by Your Name

What is Bash?

• Bash stands for Bourne Again Shell
• It’s a command-line interface (CLI) used to interact with the Linux system
• Provides tools for file manipulation, process control, scripting, and automation

Why Use the Terminal?

• More powerful and flexible than GUIs
• Allows automation and scripting
• Remote administration via SSH
• Essential for servers, development, and system management

Bash Prompt Structure

$ user@hostname:~/directory$

• user — your username
• hostname — the machine name
• ~/directory — current working directory

Basic Navigation

pwd          # Print current directory
ls           # List files
cd /path     # Change directory
cd ..        # Go up one directory
cd ~         # Go to home directory
          

File and Directory Management

touch file.txt          # Create file
mkdir folder            # Create directory
cp file1 file2          # Copy file
mv old new              # Move or rename
rm file.txt             # Remove file
rm -r folder            # Remove directory recursively
          

Viewing Files

cat file.txt            # Print file contents
less file.txt           # Scroll through file
head file.txt           # Show first 10 lines
tail file.txt           # Show last 10 lines
grep "text" file.txt    # Search for text
          

Permissions and Ownership

ls -l                    # Show permissions
chmod 755 file.sh        # Change permissions
chown user:group file    # Change owner and group
          

Example permission format: -rwxr-xr--

Process Management

ps                      # Show processes
top                     # Interactive process viewer
kill PID                # Terminate process
kill -9 PID             # Force kill process
jobs                    # List background jobs
fg / bg                 # Bring job to foreground/background
          

Redirection and Pipes

command > file          # Redirect output to file
command >> file         # Append output to file
command < file          # Read input from file
command1 | command2     # Pipe output of one into another
          

Example: cat file.txt | grep "error"

Environment Variables

echo $HOME
echo $PATH
export MYVAR="Hello"
echo $MYVAR
unset MYVAR
          

Writing Shell Scripts

#!/bin/bash
# My first script
echo "Hello, $USER!"
pwd
ls
          

Save as script.sh, make executable: chmod +x script.sh

Run: ./script.sh

Control Structures

if [ -f file.txt ]; then
  echo "File exists"
else
  echo "File not found"
fi

for file in *.txt; do
  echo $file
done
          

History and Aliases

history               # View command history
!45                   # Run command #45 from history
alias ll='ls -lh'     # Create alias
unalias ll            # Remove alias
          

Keyboard Shortcuts

• Ctrl + C – Cancel command
• Ctrl + L – Clear screen
• Ctrl + R – Reverse search history
• Tab – Autocomplete
• !! – Repeat last command

Tips and Tricks

• Use man command for help
• Chain commands with && or ;
• Use sudo for admin tasks
• Learn tmux or screen for multitasking

Summary

• Bash is powerful for interacting with Linux systems
• Mastering it improves efficiency and automation
• Explore scripting and customization next!

“The command line is where power users live.”