(Cacti are pretty cool too)
Succulents include a wide variety of genus and species and therefore come in a variety of colors, shapes, and textures. A huge advantage of succulents is that they are able to retain water in their thick, fleshy leaves and stems. The plants come in a seemingly endless selection of sizes, shapes, and colors, and can adapt to many different types of growing conditions. They also require very little care, making them a no-fail plant option.
Any plant, usually from an arid climate, that has fleshy leaves and stems to store water is considered a succulent. This includes cacti, sedum, aloe, agave, crassus echeveria, sempervivum, kalanchoe, and hundreds of other species. However, most gardeners use the term succulent to only include species with fleshy leaves. Any plant with spines is called a cactus, even though all of these plants fall under the succulent umbrella.