"What is a centerset?"
It is a lavatory set that is 4" center to center from handle to handle.
"What is a mini-widespread (4 inch centerset)?"
It is similar to a widespread but with a 4 inch center to center instead of 8 or 12 inches.
"What type of faucets can I use in the bathroom?"
The two most commonly used bathroom sink (lavatory) faucets are the 4-inch centerset and the widespread.
"What is a widespread set?"
A widespread set includes three separate parts that measure from 8 to 20 inches from center to center.