I had no idea that there was a difference between these 2 though they belong to the same family.
I posted a succulent that was about to bloom on my FB and one of my FB friends who's an expert in these plants told me that what i had was a succulent and not a cactus and even named the succulent for me. He told me that this group of succulents pollinate through flies and therefore the flowers are not very pretty and in fact have a horrid smell. Some are so bad that you cannot put them indoors.
Luckily mine which is a stapelia, doesn't have an overwhelming smellHidden Content