There is confusion about these plants. I hope this will help.
ALL CACTI ARE SUCCULENTS, BUT NOT ALL SUCCULENTS ARE CACTI!
Succulents are plants that have modified leaves, able to store water and like a hot dry climate. This is why most are found in desert areas of the world. Succulents have modified leaves and thick stems able to store water as aloes and agaves. Here are some pictures of succulents from the Sonoran and the Mohave Deserts. Here a succulent container. All these plants will survive in gardens in Boise. Kato wondered what I was doing.
This is signature plant of the Mohave Desert (Mojave) Joshua Tree
CACTI are succulents whose leave have been modified to spines and attached to the trunk by areoles.
The Christmas or Easter cacti are true cactibut found in tropical forests.
The signature plant of the Sonoran Desert is the saguaro. I don’t know where my photo right now. Any questions feel free to asked me.