Where is my disk space going?

Hey, I am pretty new to the Mac world. Just purchased my first macbook air. As of today I suddenly lost about 8GB in hard disk space. Trying to figure out where it went. I have checked the About This Mac / Disk Space and everything is as it seems. I have also noticed that the "Other" section has increased from 8GB to 20GB in the last few weeks. Is this normal? I haven't downloaded any new apps and haven't really been downloading any media files. Just a bit of web browsing and coding in Xcode (also checked these files). Just wondering how I could of suddenly lost 8GB in space! Hope someone can help.

 

Hey, just did that now. Doesn't seem to be anything old but I have just lost another 3/4gb in disk space in the last few minutes! The other folder has also gone from 20gb to 23gb! Seem like my space is being drained.

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Space is definitely being lost to "Other", not sure why though. At this rate I'll be out of space by next week.

 

This was it


1 /.DocumentRevisions-V100
1 /.fseventsd
0 /.PKInstallSandboxManager
1 /.Spotlight-V100
0 /.Trashes
0 /.vol
10 /Applications
1 /bin
0 /cores
1 /dev
1 /home
4 /Library
1 /net
0 /Network
15 /private
1 /sbin
5 /System
14 /Users
1 /usr
1 /Volumes
47 /
47 total

 

Fixed it! It was APP/OSx downloads waiting to be installed. Installed them, rebooted and vollia! 13GB back. Thanks for your help, found the problem with omni disk sweeper.