System directories don't exist for no reason, so don't start deleting them willy-nilly.
If you did this as user pi, chances are the data is in
/home/pi somewhere, but sometimes applications will also use
/tmp as it is world writable, or somewhere in
/var if they have a writable location there.1 Commonly
/tmp is actually a small, in memory directory (meaning it won't hold much and does not persist across boots) but I believe this is not the case by default on current versions of Raspbian (there are a few similar things though; you can check for such directories with
mount | grep "^tmpfs" -- but these are obviously not the problem here).
A good tool for finding this kind of thing is
du; this will give you per directory totals for a tree, e.g.:
> du -h /home/pi/temp
-h provides more "human" digestible numbers (with units). Here you can see
/home/pi/temp contains a total of 28 MB, most of it in
bearPics, most of that in
With large trees, it may be easier to use
du -h -d 1, where the
-d 1 means to show just 1 level deep; you can then analyze individual subdirectories from there. If you want to get really fancy (thanks stevieb from comments below):
du -h /home/pi | sort -n -r | head -n 10
Will show you the top 10 largest directories in descending order; logically the top one will be
/home/pi, since it includes everything inside.
Don't try this on
/ as it will take a long time. You can try it on
/home/pi, which will probably give you a long list (somewhere
-d 1 might help) but the last line is always the grand total, meaning it is easy to tell whether this is the place or not.
If not check
/tmp. There is more information on
1. If it is outside of
/home, don't delete the actual directory when you find it unless it is owned by the user whose data it contains; just delete the fat data files inside. Otherwise the application may not be able to recreate the (possibly system wide) data directory when run as a normal user.