Okay, a related question.
I always assumed that it was best to format the card in-camera so that it is formatted to the camera's specs. I see some advising formatting on the computer. Kind of a moot point for me, frankly, since I don't even have a card reader, but, is there any difference?
Of course I'm talking formatting, not just deleting. I routinely format my card once I've uploaded the images and verified the files are okay.
To be honest, I think all the popular card types use FAT32 as their filesystem now (I know there's been some push toward ext2 for microSD, but that's not really relevant to the question). I would recommend formatting in-camera only because certain cameras with certain firmware might only be designed to read/write one filesystem or another. I suspect on modern cameras that isn't much of an issue, but the point is that there is no way to format in camera and end up with a filesystem that the camera can't read, whereas it would be possible, formatting on the computer.
There's no actual way to "damage" the card by formatting it (other than normal wear from write cycles), but it's just guaranteed to work if you do it in the camera versus on the computer.
Finally, there's no need to reformat your card every time you dump images off it. Compared to just erasing all images, reformatting rebuilds the filesystem, which is unnecessary since a filesystem never "expires". The only times I'd bother reformatting is the first time you use a card, if you switch that card to primarily be used in another device, and of course if the camera is having trouble reading/writing the card. Otherwise you're just spending extra time and putting extra wear on the card for no real benefit.
Edit: As regards "the camera's specs", all major filesystems are standard, so the camera can't somehow "do something different" as regards the filesystem. The only reason that would ever happen is if the camera's manufacturer wanted to make it proprietary to force you to buy their cards (which would no longer actually be CF, SD, etc., even if they were the same shape), which none of the big manufacturers do.