Walls and Ceilings - Is Joint compound a separate thing from regular drywall mud?

I successfully repaired a drywall hole many moons ago w/ some stuff I'm assuming was drywall mud, it was gray and instructions said to add some water, and it dried smooth. that tub is long gone, so I don't remember the labeling.

I'm fixing another hole now, and the tub is joint compound. it's white, says no water added, and after I let it dry, there were a bunch of cracks.

I tend to be repair challenged, so when I find something that works, I like to stick to it. Is there a definite difference between regular drywall mud and joint compound? Thanks.

Drywall mud and joint compound are the same thing. If it's put on too thick, it often cracks when it dries. Try thinner layers and build it up slowly.

Should say somewhere on there, All-Purpose, Lite. Topping Mix, no matter what breed you've got, you really need to thin it a bit with some water, properly mixed taping/finishing mud should be a thick batter consistency, and as was previously posted here, trying to put on too much in one layer will cause cracking as well.

I'm assuming here that this is a climate controlled room right?