Ubuntu: How to free up space (disk cleanup for Ubuntu)?

To check disk usage open a terminal and type:

$ df -k

The output will show all of the partitions and the current disk usage. The "-k" says to show sizes in terms of 1K blocks, so that a result such as 517400 is approximately 500 MB.

Try the following commands to free up disk:

$ sudo aptitude clean
$ sudo aptitude autoclean
$ sudo aptitude autoremove
$ sudo apt-get autoremove