System Basic
date
Show date and time
uptime
Display system uptime
cal
Show calendar
w
Display who is logged in
whoami
Display effective username
finger user
Show info about user
uname -a
Show kernel info
man cmd
Show man page for cmd
df
Display free disk space
du
Display disk usage stats
free
Show memory and swap usage
whereis app
Show where app location is
which app
Show which app
Directories Basic
ls -l
List current dir contents (long format)
ls
List current dir contents
ls -a
List current dir contents including hidden
ls -t
List current dir contents sorted by mod date
cd
Change to home dir
cd dir
Change to directory 'dir'
pwd
Show current directory
mkdir dir
Make directory 'dir'
rm -r dir
Remove directory 'dir'
rm -rf dir
Remove directory 'dir' (force)
cp -r dir1 dir2
Copy 'dir1' to 'dir2'
cd -
Change to previous working dir
Files Basic
rm file
Remove 'file'
rm -f file
Remove 'file' (force)
cp file1 file2
Copy 'file1' to 'file2'
mv file1 file2
Rename or move file1 to file2
ln -s file1 link1
Create symbolic 'link1' to 'file1'
touch file
Create or update 'file'
cat>file
Put standard output into 'file'
more file
Output file 'file'
head file
Output first 10 lines of 'file'
tail file
Output last 10 lines of 'file'
tail -f file
Output 'file' as it grows
Search Basic
grep pattern files
Search for 'pattern' in 'files'
grep -r pattern dir
Search recursively for 'pattern' in dir
cmd | grep pattern
Search for 'pattern' in output of cmd
locate file
Find file names quickly
Shortcuts
^c
Halt current command
^z
Background current command
^d
Delete char infront of cursor or logout
^u
Erase line
^r
Search recent commands
^a
Move to beginning of line
^e
Move to end of line
^h
Delete char behind cursor (backspace)
up
Move to previous command
down
Move to next command
Processes
ps
Display your active processes
top
Display all processes
kill 5
Terminate process id of 5
kill -9 5
Terminate (KILL) process id of 5
killall proc
Terminate all processes named 'proc'
bg
List background jobs
fg
Bring most recent job to foreground
fg 2
Bring job 2 to foreground
Command History
!!
Repeat last command
sudo !!
Repeat last command as root
up
Move to previous command
down
Move to next command
!3
Execute command 3 in history
history
Show command history
Compression
tar cf file.tar files
Create a tar 'file.tar' with 'files'
tar xf file.tar
Extract files from 'file.tar'
tar czf file.tar.gz files
Create tar with gzip compression
tar xzf file.tar.gz
Extract files from file.tar.gz
gzip file
Compress 'file' with gzip
gzip -d file.gz
Decompress file.gz
