I installed Ubuntu 12.04 by doing a fresh install where there was previously Ubuntu 11.10. My computer warns me now that my disk is nearly full. After having run apt-get purge, run apt-get autoremove and emptied the Trash can, I still have this problem as shown by this screenshot of Gparted:

The disk /dev/sda7 is indeed full. I ran the Disk Usage Analyzer (Baobab) and I am still not sure of what is happening:

One of my hypothesis is that when installing Ubuntu 12.04, I didn't configure my disks well and the disk /dev/sda6 is not mounted well as /home. Is this the reason indeed? What should I do to verify this and then to get the things fixed?

Here are a few additional details to answer the questions I received (thank you everybody):

• My home directory is not encrypted.
• The Backup utility (Déjà Dup) is not set for automatic backups. (I do it myself and manually.)

• After I mount /dev/sda6, the command df -h gives

  Filesystem Size Used Avail Use% Mounted on

  /dev/sda7 244G 221G 12G 96% /

  udev 3,9G 4,0K 3,9G 1% /dev

  tmpfs 1,6G 904K 1,6G 1% /run

  none 5,0M 0 5,0M 0% /run/lock

  none 3,9G 164K 3,9G 1% /run/shm

  /dev/sda6 653G 189G 433G 31% /media/8ec2fa69-039b-4c52-ab1b-034d785132a1

(sorry but formatting this into code does not work, for an unknown reason)

• Thanks to izx's post, I realized /dev/sda6 was not even mounted before. It contains all the documents I used to have when I was running Ubuntu 11.10.