What is the Difference Between Similar But Different Things, Terms, and Objects

What is the Difference between Rdimm, Rimm, Udimm, Simm, Sdram, Dimm and Sodimm

In-line memory modules that are used as computer accessories are of various types like Rdimm, Rimm, Udimm, Simm, Sdram, Dimm and Sodimm. All these memory modules are different in terms of features as well as structures and functions.