I think I found it. I believe it was MAIL. I had not downloaded emails to computer for about a year and just started to do so because my Yahoo account wouldn't allow me to open attachments cause HD drive was too full. So although I was deleting lots of large files, the more room I made the more emails loaded in. I think I am okay now. Thank you all for your responses.
I keep getting message my Mac HD harddrive is full.
I delete files and free up gigabytes, then I start using the Mac and very shortly I have no free space again.
I finally got an external drive and moved lots over and deleted lots of files.
Next day I don't have that freed up space again.
What could be gobbling up my harddrive space?
It's messes up everything I go to do like downloading email attachments, running software. It's horrible and I can't figure out what's going on.
Any ideas? Is it a virus or something?