Show current directory
pwd
Directory listing
ls
Directory listing with hidden items
ls -al
Change to directiory “abc”
cd abc
Go back to home
cd
Make directory “abc”
mkdir abc
Copy directory “abc” to “xyz”
cp -r abc xyz
Remove directory “abc”
rm -r abc
Force remove directory “abc”
rm -rf abc
Create or update file
touch file
Remove File
rm file
Force remove file
rm -f file
Copy file1 to file2
cp file1 file2
Rename or move file1 to file2
mv file1 file2
Places standard input into file
cat > file
Output the contents of file
more file
output the first 10 lines of file
head file
output the last 10 lines of file
tail file
Output file realtime
tail -f file
Search for pattern in files
grep pattern files
search recursively for pattern in dir
grep -r pattern dir
Search for pattern in command output
command | grep pattern
Find all instances of file
locate file
Compress files to a .tar
tar cf file.tar files
Extract files from a .tar
tar xf file.tar
Compress files to a Gzip
tar czf file.tar.gz files
Compress files From a Gzip
tar xzf file.tar.gz
Host check ping
ping host
Download file
wget file
Resume file download
wget -c file
Halts the current command
Ctrl+C
Exit
Ctrl+D
Erases the whole line
Ctrl+U
SSH to a host
ssh user@host
SSH to a host on port
ssh -p port user@host
log out of current session
exit

A personal technical diary… To the point… Precise