I don't know why, but it seems like some of the pictures I have saved on my computer had gone bad. They are fuzzier than they used to be. Am I crazy or do those files deteriorate?
They don't really go bad, but may look bad for several different reasons. They might be poor resolution from a 640x480 digicam. The compression on the file in .jpg format may be pretty severe, so it fuzzes things out to use less colors and make the file size smaller. Also might be that you changed monitors or are viewing them in AOL. Yes, I have found that viewing websites and photos in AOL can make them look like ****. Just some thoughts. P.s. I'm a photoshop whiz, in the event you need any of them fixed.
Just to add to 51Leadsled's comments; jpegs are compressed files, anytime you open a jpeg and then save it the file is re-compressed. Every time this happens it loses resolution. If you open a jpeg, and don't modify it, don't "save" the file just close it without saving it. That way it won't recompress the file.