The Terminal Is Your Superpower
Every developer eventually has to work in a Linux environment — whether it's SSH-ing into a production server, running CI/CD pipelines, or just using macOS's Terminal. Fluency with the command line multiplies your productivity. Here are the 25 commands that come up most.
Navigation
pwd # print working directory
ls -lah # list files (long format, all, human-readable sizes)
cd - # go to previous directory
cd ~ # go to home directory
File Operations
cp -r src/ dest/ # copy directory recursively
mv file.txt ~/Documents/ # move or rename
rm -rf old-folder/ # delete directory (careful!)
mkdir -p a/b/c # create nested directories
touch file.txt # create empty file or update timestamp
Viewing Files
cat file.txt # print entire file
less file.txt # paginated view (q to quit)
head -n 20 file.txt # first 20 lines
tail -n 50 file.txt # last 50 lines
tail -f app.log # follow log file in real time
Searching
# Find files
find . -name "*.ts" -type f
find . -newer package.json -type f
# Search inside files
grep -rn "TODO" src/
grep -rn "function auth" --include="*.ts"
# Powerful searching with ripgrep (faster than grep)
rg "TODO" src/
Text Processing
# Count lines, words, characters
wc -l file.txt
# Sort lines
sort names.txt
sort -rn scores.txt # reverse numeric sort
# Remove duplicates
sort names.txt | uniq
# Cut columns from CSV
cut -d',' -f1,3 data.csv
# Stream editor — find/replace
sed 's/foo/bar/g' file.txt
sed -i 's/foo/bar/g' file.txt # in-place edit
Piping & Redirection
# Pipe output into next command
cat access.log | grep "404" | wc -l
# Redirect output to file
ls -la > files.txt # overwrite
ls -la >> files.txt # append
# Redirect stderr
command 2> errors.log
command 2>&1 | tee all.log # stdout + stderr to file and terminal
Process Management
ps aux # all running processes
ps aux | grep node # find specific process
kill -9 <pid> # force kill process
pkill -f "node server" # kill by name pattern
top # live process monitor
htop # better live monitor (if installed)
# Background processes
command & # run in background
jobs # list background jobs
fg %1 # bring job 1 to foreground
nohup command & # run after terminal closes
Permissions
chmod +x script.sh # make executable
chmod 755 script.sh # rwxr-xr-x
chmod -R 644 public/ # recursive
chown user:group file.txt
sudo chown -R $USER /app
Networking
curl -I https://example.com # HTTP headers only
curl -X POST https://api.example.com/users -H "Content-Type: application/json" -d '{"name":"Alex"}'
wget https://example.com/file.zip # download file
ping google.com # check connectivity
netstat -tulnp # listening ports
ss -tulnp # modern netstat
Disk & System Info
df -h # disk space usage
du -sh folder/ # size of folder
free -h # memory usage
uname -a # system info
uptime # how long system has been running
Shortcuts That Save Time
!! # repeat last command
!grep # repeat last grep command
Ctrl+R # reverse search command history
Ctrl+A # jump to start of line
Ctrl+E # jump to end of line
Ctrl+K # delete from cursor to end
Ctrl+L # clear screen
Conclusion
These 25 commands cover the vast majority of what you'll do in a Linux terminal day to day. Learn them by doing — next time you're tempted to reach for a GUI tool, see if you can do it from the command line instead. After a month of deliberate practice, the terminal will feel faster than any GUI.
