Computer Basics -1 || Introduction and Structure of Computer.

COMPUTER is derived from the word “Compute“, which means calculating something. So, in general, a Computer is an electronic device/machine which receives some input, process the data, and provides information in the desired format.

Workflow of Computer

Computer Structure

The above diagram reflects the basic structure and work-flow of a Computer. It also, shows that the CPU is the brain of the computer, which decides how to handle input and output devices.

Data and Information

Data is a collection of lots of content in the form of Numbers, characters, images, etc. On the other hand, identifying and extracting only that data which is useful for us is known as Information.

In simple, Information is a processed version of the Data.

Input Devices

Input devices like Keyboard, Mouse, Touch screen are used to give inputs or feed data into the computer system.

Output Devices

Output devices like Monitor display, Speaker, Printer, etc. are used to get information after processing.

CPU (Central Processing Unit)

CPU is the brain of the computers. It provides a connection between Input devices, Output devices and Memory of the computer. All these components remain connected via Motherboard.

CPU Processing

A Motherboard is a chip-set to connect all these components and also, help for intercommunication. Below are the different Units embedded within a standard CPU:

MU (Memory Unit)

It controls all types of memory in a computer. There are mainly three types of Memory.

HDD (Hard Disk Drive) or Permanent Memory

Basically, HDD stores all the data including Operating System, Installed Software, Applications, Files, Folders, etc. Size of this type of memory would remain in GB(Gigabytes) and TB(Terabytes).

RAM (Random Access Memory)

As we know, HDD stores all the data in memory. But at run-time, we need only a few files or application for the processing. RAM is used to access these type of files from the HDD to increase the speed and performance.

To understand the difference between HDD and RAM, take a simple example. Suppose you have a table with a drawer. Consider, the drawer is like an HDD which contains lots of files. If we want to work on a specific file, we need to pull out that file and put the same on the table to open and work in it. So this table would be like RAM. You can open multiple files on the table till it has space, after that you have to free up space by closing the files.

ROM (Read Only Memory)

The above memories HDD and RAM would be active and available only when the system is ON and logged in by the user. But you know, when we start the computer there is another type of memory which has been used to boot and reboot the system.

Booting is a process of loading the operating system and all the required application in the memory for the user. After Booting, the first program that runs is called BIOS (Basic Input Output System).

  • Cold Booting: When the system is started first time by Switching ON, is called cold booting, after that BIOS runs.
  • Warm Booting: When the system is already running and needs to re-started, called warm booting. In this case, BIOS is not reloaded.

ALU (Arithmetic and Logical Unit)

This unit performs all the processing work. It takes the input from the Control Unit, performs all types of calculation, validation and decision work and sends the output to the Control Unit.

CU (Control Unit)

Control Unit, identifies the input and output devices. It takes input from the user in the form of the Data. Share this data with ALU for processing. After that sends this data to the Output device so that the user can view the output.

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            Ashok Kumar is working in an IT Company as a QA Consultant. He has started his career as a Test Trainee in manual testing in August 2010. Then he moves towards the automation testing after 4 years. He started learning JAVA and Selenium by self to get the knowledge of automation.

       While learning these tools and working on multiple projects, he found that sometimes people get stuck in live scenarios in their project and they have to do lots of RnD to get out of it. So he decided to start blogging only for such scenarios, where anyone facing any problem in their project, can ask any question or give a solution or you can say an alternate solution to achieve the goal successfully.

Later on, he observed that some people want to learn Java but they have few questions in their mind like how to start Java, whether we should go for the online or offline course. So he started writing tutorials on Java, Jira, Selenium, Excel etc.