A motherboard =  central printed circuit board (PCB) =  mainboard =  system board =  Applelogic board = mobo.

The motherboard’s main job is to hold the computer’s microprocessor
chip and let everything else connect to it. Everything that runs the
computer or enhances its performance is either part of the motherboard
or plugs into it via a slot or port.

The essential motherboard make-up includes the chipset (known as the “glue logic“), some code in ROM and the various wired interconnections between the components know as buses.
The chipset is fundamental, and controls how the motherboard interacts
with everything else in the system. A good chipset can be more
important than the power of CPU or the amount of RAM. The ROM code
includes the BIOS, which has user-changeable options for how the
motherboard operates with integral and connected devices.

 Motherboard Standard  :

1-Form factor is the shape and layout of a motherboard ,The form factor affects where individual components go and the shape of the computer’s case.

2-  Socket for the microprocessor determines what kind of Central Processing Unit (CPU) the motherboard uses.

3- The chipset is part of the motherboard’s
logic system and is usually made of two parts — the northbridge and
the southbridge. These two “bridges” connect the CPU to other parts of
the computer.

4- (BIOS) chip controls the most basic functions of the computer and
performs a self-test every time you turn it on. Some systems feature
dual BIOS, which provides a backup in case one fails or in case of
error during updating.

5-The real time clock chip is a battery-operated chip that maintains basic settings and the system time.

The slots and ports found on a motherboard include:

1- (PCI)- connections for video, sound and video capture cards, as well as network cards

2-Accelerated Graphics Port (AGP) – dedicated port for video cards.

3-Integrated Drive Electronics (IDE) – interfaces for the hard drives

4-Universal Serial Bus or FireWire – external peripherals

5-Memory slots