ALU: The Arithmetic Logic Unit is a subset of the CPU that performs all computer code operations after they've been broken down into simple arithmetic or logical comparisons.

BIOS: Nope, this doesn't have anything to do with that homework you had writing a detailed report on the inventor of paper bags. The Basic Input Output System is firmware that comes pre-installed on a computer’s motherboard. It's the first thing that's activated when your PC boots up.

Bit: A BInary digiT: 0 or 1. A bit is the abstraction computer scientists use to represent the on or off, charged or un-charged state of an electric component.

Byte: The main unit of computer memory, made up of eight bits each. Yup, it's that small.

CMOS: A Complementary Metal Oxide Semi-conductor is a chip on the motherboard that uses a teensy amount of energy (taken from a battery when the computer’s power is off) to give continuous power to the computer clock.

Compiler: A software program that translates the statements of a program into a lower-level language that the computer can understand. Every programming language that isn't exclusively numbers (so, uh…all of them) has its own unique compiler.

Computer: An electronic machine that can take in inputs and return outputs based on them.

CPU: The Central Processing Unit, often just called, "the processor," is the brains of a computer. It's made of electronic parts that figure out how to store and process program instructions—along with their data.

Driver: Every piece of input and output (like a printer, mouse, or keyboard) has a device driver. The driver identifies the characteristics of the device to the computer so that the computer knows how to work with with it.

GUI: A Graphical User Interface is software that allows a computer to communicate with a person using images and buttons. Think: the screen of the monitor you're using to read this page.

Firmware: Firmware is computer software that sits permanently in a computer’s hardware.

Hardware: In the technology world, hardware could be any physical piece of equipment or electronics that can be used with other pieces of hardware to make a computer.

Hard drive: The Hard Disk Drive (HDD), usually just called "the hard drive," is memory in the computer that stores all the user-loaded applications. That includes the operating system, computer applications (software), and any user files that get accessed all the time.

Interrupt: A request from the OS to have the CPU put what it's currently doing on hold temporarily so that it can process something more pressing like an input or output device request.

Motherboard: The primary circuit board inside a PC. All computer hardware components connect through the motherboard.

Operating System (OS): A collection of software utilities that link the computer‘s different components (like the CPU, memory, application software, and any hardware devices) together. It has 3 primary functions:

1. Manage the computer’s hardware and software resources in order to maximize CPU usage and storage capacity.
2. Handle communications between applications and the computer’s hardware, making sure that each request gets as much processor time as it needs, and if interrupted, gets rescheduled for more CPU time. 
3. Take care of any messages traveling between the user and the applications they're using.

POST: The Power On Self Test procedure is run by BIOS when the computer gets powered on, confirming that all of the hardware components are there and running.

Process Control Block (PCB): A data structure that holds addresses and memory block sizes. It's used by the CPU to figure out where it last left off or where it needs to go next.

RAM: Random Access Memory is only available when the computer's on. It temporarily stores numbers, instructions, and addresses the computer needs until the software tells it to pick up the info and use it.

Register: An area in the CPU that acts like storage despite not technically being storage. These are just small spaces on the CPU that hold some data while the CPU's actively using it. Unlike storage, registers don’t let data sit around. It might hold the results of computations or an address that points to a piece of data the CPU's going to need in a couple of minutes while the program's running.

ROM: Read-Only Memory stores information that can't be changed. This is the stuff that the computer needs to reference over and over like running BIOS.

Software: A collection of instructions that direct a computer to perform some function. When you hear workds like

• program
• code
• application, or app

you're probably listening to someone talking about software. That, or they're pulling buzzwords out of nowhere to sound cool and tech-y.

Transistor: A tiny piece of hardware that acts like an electronic gate, managing the flow of electric current.