linux command

Check size directories

$ du -sh *

Search file

$ sudo find [path] -name "[filename]"

Unzip tar.gz using tar command

$ tar -xvzf filename.tar.gz

f: this must be the last flag of the command, and the tar file must be immediately after. It tells tar the name and path of the compressed file.
z: tells tar to decompress the archive using gzip
x: tar can collect files or extract them. x does the latter.