I started using Linux as my operating system many years ago — I believe it was in the early 2000s. Over the years, I’ve used several distributions, from Mandrake Linux to Ubuntu and Debian. Currently, my favorite is Manjaro Linux with the KDE desktop environment. For most of this time, I used the default Bash shell, but for the last 2–3 years I’ve been using Oh My Zsh — partly because I also have a Mac, and I installed it there as well. Most of the commands I know in the terminal I originally studied many years ago. That’s why I’ve added 5 minutes to my daily routine to either review a Linux command or learn a new one. I’m doing the same for Oh My Zsh aliases and functions — with the help of ChatGPT. Below, I’ve included the commands in a table.

Linux One Command Per Day

Command	Description	Examples
tldr	Get command description.	tldr ls
bat	Advanced alternative to cat, with syntax highlighting and line numbers. Useful for reading code or config files.	bat file.txt bat script.sh cat file.txt | bat
cat	Displays the contents of one or more files, or concatenates them. Useful for quick viewing or merging files.	cat file.txt cat file1.txt file2.txt cat file1.txt file2.txt > merged.txt cat /etc/passwd | less
grep	Searches for a pattern in files or input. Supports regular expressions. Use -i for case-insensitive search.	grep 'error' logfile.txt grep -i 'warning' logfile.txt cat file.txt | grep 'pattern' grep -r 'TODO' src/
du	Displays disk usage of files and directories. Add -h for human-readable sizes and -s to summarize.	du -sh ~ du -sh * du -ah /var/log | sort -rh | head -10 du -c *.txt
xargs	Reads input and passes it as arguments to another command. Useful in pipelines or when dealing with long lists.	echo "file1.txt file2.txt" | xargs rm find /var/log -name "*.log" | xargs rm find . -name "*.jpg" | xargs -n 1 -I % cp % /backup/ find . -print0 | xargs -0 ls -lh
find	Searches for files and directories based on name, type, size, permissions, and more. Very powerful for recursive search and cleanup.	find ~ -name "file.txt" find /tmp -name "*.tmp" -delete find / -size +100M find . -type f -mtime -1 find . -name "*.bak" -delete
rsync	Efficiently synchronizes files and directories. Ideal for backups and remote copies.	rsync -av source/ destination/ rsync -av --delete ~/Docs/ /mnt/backup/ rsync -avz -e ssh ~/Docs/ user@host:/backup/ rsync -av --progress bigfile.iso /mnt/backup/
ncdu	Interactive disk usage viewer. Great for finding large files and folders quickly.	ncdu ncdu /home ncdu /var/log
tmux	Terminal multiplexer: split windows, manage sessions, run processes in background.	tmux tmux new -s session_name tmux attach -t session_name tmux list-sessions
fzf	Fuzzy finder to search files, history, directories interactively. Super fast.	fzf history | fzf find . -type f | fzf | xargs nano cd $(find . -type d | fzf)
z	Jump to frequently used directories. Learns your habits over time.	z projects z dev z -l
cut	Extracts columns or characters from text. Useful for processing structured output.	cut -d',' -f1 data.csv cut -c1-5 file.txt cut -d':' -f1 /etc/passwd ls -l | cut -d' ' -f9
sort	Sorts lines of text alphabetically or numerically. Combine with uniq for cleanup.	sort file.txt sort -n numbers.txt sort -r file.txt sort -t',' -k2 file.csv
uniq	Removes or identifies duplicate lines. Input should be sorted for best results.	sort file.txt | uniq sort file.txt | uniq -c sort file.txt | uniq -d sort file.txt | uniq -u
awk	Powerful text processor and mini language for field-based data manipulation.	awk '{print $1}' file.txt awk -F',' '{print $2}' data.csv ls -l | awk '{print $9}' awk '/error/ {print $0}' logfile.txt
head	Displays the first lines of a file. By default, shows the first 10 lines.	head file.txt head -n 20 file.txt ls -lh | head -n 5 head -c 100 file.txt
tail	Displays the last lines of a file. Great for monitoring logs in real time.	tail file.txt tail -n 20 file.txt tail -f /var/log/syslog tail -n +5 file.txt
wc	Counts lines, words, and characters in a file or input. Use with pipes or files.	wc file.txt wc -l file.txt wc -w file.txt ls | wc -l
basename	Extracts the filename from a full path. Useful in scripts to isolate filenames.	basename /home/user/file.txt basename /var/log/syslog basename /path/photo.jpg .jpg filename=$(basename "$1")
dirname	Extracts the directory path from a full file path. Often used in shell scripts.	dirname /home/user/file.txt dirname /var/log/syslog dir=$(dirname "$1") echo "Folder: $(dirname "$filepath")"
tee	Reads from standard input and writes to both standard output and a file.	echo "Hello" | tee output.txt ls -l | tee filelist.txt echo "Line" | tee -a log.txt echo "127.0.0.1 example.com" | sudo tee -a /etc/hosts
diff	Compares two files line by line. Great for spotting changes or debugging configs.	diff file1.txt file2.txt diff -i a.txt b.txt diff -y file1 file2 diff -r dir1 dir2
chmod	Changes file or directory permissions using symbolic or numeric modes.	chmod 755 script.sh chmod u+x script.sh chmod 444 readonly.txt chmod g-w file.txt
ps	Displays information about active processes. Use aux for full details.	ps ps aux ps -u $USER ps aux | grep python
kill	Sends signals to processes by PID. Typically used to stop or restart processes.	kill 12345 kill -9 12345 pkill firefox kill -l
which	Shows the full path of the executable that would run for a given command.	which ls which python3 which git which node
env	Displays environment variables or runs a command with a modified environment.	env env VAR=value command env DEBUG=1 python script.py env -i bash

Oh My Zsh Aliases

to do :)