Hot answers tagged hard-drive
I use Daisy Disk to keep tabs on what's using up space on my disks. Like @Hoshts and @Joonas have mentioned in their comments on another answer it's not free, but gorgeous and easy to understand. Money well spent, in my opinion, unless you're just looking for a one-time solution.
You have memory leak somewhere and it's causing your system to essentially supplement ram with hard drive. Open activity monitor, go to the memory tab, and sort by usage. See if you can figure out what program or combination of programs is gobbling up all your memory. Also that same tab will show you used memory, swap space, etc.
Use the program called Disk Inventory X. It has a nice GUI which will show you exactly what files and folders are taking up the most space. Disk Inventory X
My favourite tool for this is http://grandperspectiv.sourceforge.net/ which gives a great graphical representation of files. In your particular case, I have encountered issues with smaller "Solid State Drives" like those used in earlier MacBook Air system, where the system does not completely free up filespace on the SSD when some things have been deleted - ...
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