A Cypherpunk’s Blog

Just a simple minimalist blog of a cypherpunk wannabe.

Linux Commands

Linux Terminal Commands Cheat Sheet

A quick reference for the most common and useful commands in the Linux terminal. 🐧

📂 File & Directory Management

Command Description Example
ls Lists directory contents. ls -la (lists all files, including hidden, in long format)
cd Changes the current directory. cd /home/user/documents
pwd Prints the current working directory. pwd
mkdir Creates a new directory. mkdir new_folder
rmdir Removes an empty directory. rmdir old_folder
touch Creates an empty file or updates its timestamp. touch new_file.txt
cp Copies files or directories. cp source.txt destination_folder/
mv Moves or renames files or directories. mv old_name.txt new_name.txt
rm Removes files or directories. rm -r old_folder (removes a directory and its contents)
cat Displays the content of a file. cat file.txt
less Views file content one page at a time. less long_file.log
head Displays the first few lines of a file. head -n 5 file.txt (shows the first 5 lines)
tail Displays the last few lines of a file. tail -f /var/log/syslog (monitors a file in real-time)

🛠️ System Information & Management

Command Description Example
uname -a Displays detailed system information. uname -a
hostname Shows the system’s hostname. hostname
df Shows disk space usage. df -h (human-readable format)
du Shows file and directory space usage. du -sh /var/log (summary of a directory’s size)
free Displays memory usage. free -m (shows usage in megabytes)
uptime Shows how long the system has been running. uptime
date Displays the current date and time. date
shutdown Shuts down or reboots the system. sudo shutdown now or sudo reboot

👤 User & Permissions Management

Command Description Example
whoami Shows the current user. whoami
sudo Executes a command with superuser (root) privileges. sudo apt update
su Switches to another user account. su - username
chmod Changes the permissions of a file or directory. chmod 755 script.sh (sets read/write/execute for owner, read/execute for others)
chown Changes the owner of a file or directory. sudo chown user:group file.txt

⚙️ Process Management

Command Description Example
ps Lists currently running processes. ps aux (shows all processes for all users)
top Displays a real-time, interactive list of processes. top
kill Sends a signal to a process (e.g., to terminate it). kill 1234 (sends TERM signal to process ID 1234)
killall Kills processes by name. killall firefox
& Runs a command in the background. gedit &

🔍 Searching & Text Manipulation

Command Description Example
grep Searches for a pattern in text or a file. grep "error" /var/log/syslog
find Searches for files and directories. find . -name "*.txt" (finds all .txt files in the current directory)
wc Counts lines, words, and characters in a file. wc -l file.txt (counts lines only)
sort Sorts the lines of a text file. sort names.txt

🌐 Networking

Command Description Example
ip addr Shows IP addresses and network interfaces. ip addr show
ping Checks connectivity with another host. ping google.com
wget Downloads files from the web. wget https://example.com/file.zip
curl Transfers data from or to a server. curl -O https://example.com/file.zip
ssh Connects to a remote host securely. ssh user@remote_host

📦 Archiving & Compression

Command Description Example
tar Creates or extracts archive files (.tar, .tar.gz, etc.). tar -czvf archive.tar.gz /path/to/dir (creates); tar -xzvf archive.tar.gz (extracts)
zip Creates .zip compressed archives. zip archive.zip file1.txt folder/
unzip Extracts files from a .zip archive. unzip archive.zip

⌨️ Terminal Shortcuts & Symbols

Shortcut/Symbol Description
Tab Autocompletes commands, file names, or directory names.
Ctrl + C Stops (interrupts) the current command.
Ctrl + Z Suspends the current command.
Ctrl + D Logs out of the current session (like exit).
!! Executes the previously run command.
` ` (Pipe)
> (Redirect) Redirects command output to a file (overwrites). Ex: ls > file_list.txt
>> (Append) Redirects command output to a file (appends). Ex: date >> log.txt