Don't know what is using all my memory

[BleachedOut]

I have used 219 GB on programs and atleast 25 GB in Videos and Pictures, I have a 1TB Hard drive and I am allowed to use 930 GB, but apparently I only have 57.8 GB left. This doesn't make any sense to me as I don't know what is using up the rest of the HDD. Now I continuously have to uninstall programs I want to use in order to free up more space on my Drive. Please help me resolve this issue as it has been annoying me lately. Thank you.

 

[CountMike]

You could try a thing like this to see where most space is taken: http://www.majorgeeks.com/files/details/treesize_free.html