# Introduction to computing – The PC

This computing fundamentals theory course is made for beginners in business field.
You will learn the basic technology and computing concepts by discovering the PC, and how it is built and organized.

Let’s  open the door to the wonderful world of computing by following this visual tutorial.

## What is a PC?

This abbreviation simply means personal computer (Personal Computer).

Today, a computer can exist in different forms: desktop, laptop, Tablet PC, and even a cell phone.

Here is a representation of a typical desktop computer. It consists of central unit and peripherals.

• All the material parts are called HARDWARE.
• Computer programs are called SOFTWARE.

### The central unit

It is also called tower, and it contains the vital organs of the computer:

• Motherboard: the plate with electronic microchips which links the essential components together and makes them work.
• Processor (CPU): the brain of the computer. It processes and executes the commands.
• Memory (RAM): stores data during its use, on a temporary basis.
• Video card: allows to project information to the screen.
• Sound card: projects sound to speakers
• Hard disk: stores and keeps the data on an ongoing basis.

### Peripherals

These are all external components or devices (in addition) which are: printer, router, monitor, mouse, webcam, speakers and so on.

### Organization and processing of data

Computers enable us to work with various informations: numbers, texts, images, sounds, videos, – called data.

Electronic data is represented internally in the form of bits (binary digits). A bit is the smallest unit of information that exists and takes the value of 0 or 1. It is also a binary variable:

• True or false
• Current passes or does not pass

Each letter or number are for the machine a sequence of 0 and 1.

Our goal is not to dwell on this complex topic in this article, but to introduce this basic concept to explain the data storage capacity measures.

### Data Storage

So-called digital data are material, physical, tangible, measured in bytes. A byte is equivalent to 8 bits. And then we can talk about:

•     kilobyte (1024 bytes)
•     megabyte (1024 KB)
•     GB (1024 MB)
•     Terabyte (1024 GB)

Why 1024?

-They are multiples of 8.

Your computer informs you of the maximum storage capacity of your hard disk, volatile RAM (Random Access Memory), graphics card (it also stores the data while it is running).

### Executing commands

Typically, your computer executes commands in a predefined order, one after another, in single line. But as nowadays processors are very fast (they execute millions of instructions per second), it seems that everything happens simultaneously and you can not see the difference in milliseconds.

What happens when you do simple arithmetic?

The PC uses his volatile RAM. It reserves within a space for number1 and number2 to another space. Another space is reserved for the result.
When you close the calculator and go on the Internet, the freed memory space is allocated to your browser.
And the higher is the number of applications running simultaneously, the more your computer gets slow. Guess why?

Running out of memory!

So when you buy a computer, its power is determined by the capacity of the processor and memory.

### The Operating System

To interact with your computer you need some user friendly interface. It is called OS, standing for Operating System.

The operating systems takes your commands as Input, and after executing and transforming data into information, returns the results to you as Output.

We will cover the introduction to OS in another lesson.

This actually covers the basics of computing.

To conclude we have some additional bonus for you as visual presentations of 2 chapters from Peter Norton’sIntroduction to Computers” book, which is in our opinion a great complementary to your knowledge.

Part 1

Part 2