The body is the basic building block which doesn't have a separate frame.
A complex body shell shown in the following picture is the main structural platform to which all the other systems are attached.
It is a modern unitized body.
The doors,the instrument panel,the seats,and other interior trim pieces are all added to the basic body shell.
The following picture shows some of the subassembly used to attach engine,drivetrain,suspension,and steering systems to the basic body structure.