There are a lot of names for seats and confusion around what they mean, so here's a simple breakdown of what's what.
Bucket Seats - 2 passengers
This refers to a two seat layout with a space in between, often with a console in the middle. This is the layout seen in the vast majority of the front seat of cars. This can also be referred to as a 40-console-40. This layout is also referred to as "captains chairs".
Full Bench Seat - 3 passengers
Often just called a bench seat, a straight seat, or a straight bench, this is a single solitary cushion that goes across 100% of the width of the vehicle.
Split Bench Seat - 3 passengers
This is one of the most common layouts. This is when the seats are split into two or three sections. Types of split bench seat are listed below.
This is a three seater bench in three separate sections. The numbers refer to an approximate percentage that each seat takes up of the vehicle. There will be three separate lower cushions and three separate leanback cushions.
This is a three seater bench seat in two sections. Typically the drivers seat is independent and seats only one, and the passengers seat fits an outer passenger plus a center passenger. There are some vehicles that make the drivers seat the larger section.
The small center seat between two larger outer seats is often referred to as a "jump seat", "buddy seat", "console seat", or "jumper seat". These are typically much more narrow than regular seats with the average jumpseat being 11"-15" in width.