mother board: main part of computer
all connections to this

RAM random access memory
solid state hard disk

LAN  local area network.

Cache Memory faster version of RAM
Level 1 Fastest type
Level 2 slower than level 1.

BIOS (Basic input output system)    a set of computer instructions in firmware that controls input and output operation, Very basic programming (BIOS controls POST)

POST power on self test

BOOT SEQUENCE Starts the operating system (Booting instructions)

OS Operating system