The part of the computer that performs calculations that enable you computer to function and is sometimes referred to as the brain of the computer is

Components directly attached to or to part of the Motherboard include: The CPU (Central processing unit), which performs most of the calculations which enable a computer to function, and is sometimes referred to as the brain of the computer.

Placeholders  are the containers in  layouts  that hold such content as  text  (including body  text, bulleted lists, and titles),  tables,  charts, smartart graphics, movies, sounds, pictures, and clip art.  slide layouts  also contain the theme (colors, fonts, effects, and the background) of a  slide.