4 Types Of Dimmers :
1. Incandescent/Halogen
2. Magnetic Low Voltage (MLV)
3. Fluorescent
4. Light Emitting Diode (LED)
These are the different types of switches :
1. A single-pole switch controls lights from a single location. ...
2. A 3-way switch provides two separate control locations and is best used with recessed lights. ...
3. A 4-way switch provides for three or more dimming locations.
4. Switches are wired to the "hot" conductor in a wall box.
I hope that my answer helps!