Do You Know Where We Store our Computer Data?

Storage devices are the devices where we electronically store/record data in the computer. Storage devices can be removable or non-removable depend on their type. Most commonly used storage devices are non-removable  can be found inside of CPU casing. Storage devices can be classified into 3 three different categories Primary, Secondary and Tertiary storage devices. These devices are non-volatile storage devices means they don't lose data when powered off. Before we move on you may already know that computer does any kind of data transferring in form of bits (0,1). Some of the common storage devices are:

 

1. Floppy Disk Drive

Floppy disk drive is basically an input/output device. It was one of the most popular storage device of the past and still it is for some people. However, today USB flash drives replacing it as one of the better alternative of floppy disk drives. Floppy disk is basically a circular shaped flexible plastic which closed inside a solid plastic cover layered with soft foam on both sides.

One of the main reason of floppy disk’s popularity is the cheap price and capability of data read/write. The data stored in floppy disk is portable and you can transport it to any other computer that has floppy disk drive installed already. Floppy disks are getting rare now, because of high data corruption rate, slow data transfer (read/write), and very small data storage capacity of only up to 1.44 Megabytes which is one of the biggest disadvantage of it. Anyways, It could still be a good option to make the backup of your small documents like a Microsoft Word document or some low-resolution images, etc..

You may wonder that some businesses and industries still regularly use floppy disk drives. Personally I had seen someone installing Windows 3.x using four floppy disks for embroidery machines.

 

2. Hard Disks or HDD:

A Hard disk consists of one or more circular disks of aluminum or other metal alloy coated with magnetic material on both sides. It’s a mass storage device capable to store large amount of data for long time-period with higher data transfer rate (read / write data). That’s why an HDD is the most common part of any system. A hard disk is commonly a Fixed disk since they can be found inside of a CPU casing, but lacks in capability of moving data from one to another place.

Note: We use portable hard drives (or External HDD) which allows to move large amount of data anywhere stored inside of an external HDD.

One of the greatest speed factor of hard disk is instead of reading the stored data inside a hard disk from the beginning it directly reaches to the exact location where data is actually stored (i.e direct access device). A hard disk can be used to store OS files, applications, files and folders etc. We'll discuss about hard disk speed factors to help you to buying good quality hard drives.

3. Optical Storage Media:

i) CD ROM (CD-R and CD-RW)
CD ROM is an abbreviation of Compact Disk Read Only Memory also a common storage device. As we said above hard disk drives read/writes data at much faster rate than a floppy disk, then why we still need a CD ROM, and the simple answer is a CD can store up to 700 MB of data in it and allows to move CD data from one place to another with ease and portability. On the other hand, floppy disk can store up to 1.44 MB which is not just enough today. It's also very cheap to buy a CD and software development companies are selling their softwares in CDs. You can get a complete version of of their softwares within single CD.  

Let's give you an example, in past when CDs were not available Microsoft Office had supplied with 32 floppy disks, But thanks to the invention of optical storage media and CD ROMs now this software is available in one CD or DVD for latest versions. You can install softwares from CDs more quickly than a floppy disk drive due to better data transfer rate of CD ROMs.

CD-R: Used for read-only data, allows one-time data recording on the disk.  It’s an abbreviation of Compact Disk Recordable.

CD-RW or CD Burner: Used for reading / writing / erasing of data to a CD more than once. CD-RW is an abbreviation of Compact Disk Re-writable. You need a classified CD-RW disk not just a CD-R disk for recording/erasing data multiple times. Remember that, a CD-R disk can only be used to record data once. Many people forget this when when buying compact disks for the same purpose.

ii) DVD ROM (DVD-R and DVD-RW)
A DVD drive can store much more data than a CD can. An average DVD can store up to 4 GB of data however the latest dual-layered DVDs are capable to store up to 8 GB of data. The main purpose of DVD drives to store movies, games or any other stuff beyond the capacity of a CD. You need a DVD ROM to to read these disks. Like CDs DVD drives also come in two types: DVD-R, DVD-RW / DVD Burner; one for just reading the disk and other for data reading and writing both.

4. Flash Memory / Pen Drives:

A USB Flash drive is a portable or removable data storage device that allows you to move data anywhere and  give immediate access to the data (because of plug and play support). They’re compact in size not bigger than a human finger can easily slide into your pockets and capable to store data anywhere from 256 MB to 512 GB.

It’s a better way to transport your data whenever you want and wherever you want . These devices are considered as backup devices and are also known as thumb drive / pen drive / Keychain drive and solid state drive (SSD the technology used in camera and smart phones and other devices – unlike HDD it stores data in integrated circuits & chips without movements of parts). USB flash drives are cheaper than a floppy disk as compare to data storage space they offer.

 

5. Magnetic Tapes / Tape Drives

Tape drives have been using for decades regarded as the most popularly used storage device ever. These devices store data using tape or cartridge coated with magnetic material provide low-cost data storage than any other disk drive can offer. These storage devices specifically used as a backup data storage. Magnetic tapes are very slow at data transfer due to sequential read/write mechanism.

Thanks for reading this article, If you want any addition/correction or suggestion to this article. Please feel free to share your thoughts in comments.

To Download this article in Urdu then click below:

Download Chapter03: Introduction to Storage Devices in Urdu
(PDF eBook) 

Read More

What are the Output Devices? ~ Urdu Guide

As you’ve learned that data processing in computer based on three main steps, first Input of data using input devices, then processing in central processing unit and finally output devices show us processed data in form of information on output devices like Monitor, Printer, etc. We can simply define output devices as the devices that are used to present the processed data in form of simple understandable information such as Monitor or Printer.

 

 

Monitor is the most common output device you’ll find in the computer that show you output of the processed data from Central Processing Unit on the monitor screen. Today, other than Monitor there many types of output devices for a computer are available in many forms, like Printers, Fax machines, Modems, Plotters, CDs, etc. And we mainly distinguish them in two types: A hard-copy output devices, soft-copy output devices.

 

MOST COMMON EXAMPLE OF OUTPUT DEVICES: MONITOR

Monitor is a Soft-copy  output device, and it’s the most common output device that connected to the computer. The information we sent to the central processing unit using input devices we see them in processed form on the monitor screen. It means that whatever work we do on the computer we can see it on the monitor screen. You can see the text, pictures, moving pictures like movies on the monitor screen.

 

To Download this article in Urdu version then click below:

Download Chapter 03: What are the Output Devices and their jobs?

<<< Next: Do you know where we Store Data into the Computer???… >>>

Read More

An Essential Guide to Central Processing Unit Components

Central Processing is most essential component of computer and whenever we say CPU our basic mean is the Processor the brain of the CPU. But we know that there are many other components inside the CPU that work together inside to do the work that CPU does for a Computer. This guide will give short brief introduction to components inside the computer.






Before we move on it's better to give the list of essential components inside CPU and we'll discuss on each one-by-one but very short:

• Motherboard or simply MOBO
• Computer Chips
• Microprocessor
• Expansion Slots
• Computer Memory or RAM Banks or Slots
• ROM BIOS
• CMOS Battery
• Additional / Add-on Devices
• Display Card
• Sound Card
• Modem
• LAN Card
• Peripheral Devices
• Ports
• Universal Serial Bus
• Power Supply

Motherboard:

Motherboard is a very large print circuit board (PCB) that is fixed inside of CPU. You'll find many kind components fixed on the motherboard and remember that without motherboard CPU there is no importance of CPU, it's just like considered as a metal casing and nothing else. Importance of Motherboard for a CPU is similar as the importance of CPU for a Computer. Every of the component attached to the motherboard can communicate with each other (e.g. Mouse click to play a sound, means mouse actually communicate with sound device to get this music playing task done).







Any motherboard consists of following components that are fixed to it:

i) Computer Chips

There is a set various kinds of ICs (Integrated circuits or Computer chips) inside any motherboard that work together to manage and control computer. In this set of IC's Microprocessor (CPU) and other chips are included that control the flow of data inside computer.

ii) Microprocessor

Microprocessor is an IC that is actually known as CPU. It does all kind of mathematical operations and processes every single instruction sent by input devices. Microprocessors gets the input from RAM to process it and then send all processed data to RAM again. That's the way microprocessor acts as a central part of the CPU casing.





It's a fact that the working speed of any computer (speed of data processing) depends upon the working speed of microprocessor chip attached to it. Every microprocessor has it's own model number and working speed or Clock-speed. Microprocessor's speed measures in Mega Hertz (MHz) or Giga Hertz (GHz). Every microprocessor today can able to process one or more tasks at a time.

iii) Expansion Slots

Those specific slots that allows you attach additional devices to your motherboard, and are known as Expansion Slots. We fix computer cards (PCB) into the

Expansion slots so that these cards immediately connected to the motherboard to work together with other devices. Basically purpose of expansion slots is to increase the capabilities of a computer a bit more or increase functionality of a computer (e.g. I want to play latest games then I definitely need a better graphics capabilities of computer so I need a better Graphics Card that will fit into the expansion slots to do the job I want).

There are various sizes of slots known such as 8-bit, 16-bit, 32-bit and 64-bit slot. Slots with bigger size means data communication between microprocessor and expansion card will be fast or in less time. There was a day when we've had only two types of slots ISA and PCI. ISA the 16-bit slot and PCI the 64-bit size slot.

But Today there are some new expansion slots are there are AGP and PCI Express. the PCI Express slot has become the most popular expansion slot today that communicates with processor more faster and efficiently. Unfortunately AGP slots are rare now because PCI express beat them so badly.

iv) Computer Memory or RAM Banks or Slots

RAM slots are the places where fix our RAM chips. RAM chips are used to store computer memory (in form of bits) temporarily that helps to keep the software running on to the computer. RAM is a primary data storage device and classed as volatile memory due to losing data after power off.

v) ROM BIOS

BIOS is an abbreviation of Basic Input Output System. BIOS is the most essential/important program of any computer that controls the computer hardware. it has stored the basic memory of a computer that contains information about the devices connected the computer. Whenever you power on the computer initially BIOS is the program that runs first and read setting of computer and POST (Power on Self-test) confirms these settings.

BIOS is a ROM chip that is usually fixed into motherboard permanently, this chip has the BIOS programs stored in it. If in any case BIOS program corrupts then your computer will become unusable. However, you can fix it but only after some hard efforts. ROM is a non-volatile memory.


vi) CMOS Battery
There is small battery fixed inside the motherboard which allows to keep store the most important information (e.g. Computer Date/Time) of a computer even when it's turned off. When you turn off the computer then this battery (CMOS chips) starts doing it's work to keep these information stored. CMOS is kind a small computer memory. As you turn on the computer then CMOS battery work finishes here.


vii) Additional / Add-on Devices:
Add-on devices are the devices that perform specific function into the computer that usually not available in your computer right now. But these are unnecessary to run a computer. However you may need such add-on devices to perform a specific the function for example display card to see output of computer, Listen sound with sound card. Add-on devices are physically in the form of a print circuit board that you fix into the Expansion slots.

Sometime a computer already have a built-in VGA port (Video graphics array) then you don't need have another expansion card for graphics device, but again you may need this run high-end application or game. We use various kinds of additional devices for example Graphics Card, Modem, LAN, etc. For this you've to buy the required card and place in any of available relevant slot.

Below we're discussing about some of important additional devices:


Display Card - You should know that to see display of any computer is not just depend on the monitor, but also you should have a display adapter (Graphic Adapter, Video Card, Video Controller) installed into the motherboard. It's the display adapter that shows the output of program running inside the computer on the monitor screen. It's possible that your computer have a built-in display adapter or video port however you can also install Display Adapter card into the expansion slots.

There are four types of graphics adapters: (i- Integrated - built-in to the motherboard, ii- PCI can only fix into PCI slot, iii- AGP - these slots are rare now, iv- PCI Express currently the most popular slot for graphic adapters). There are three common connectors: VGA, SVGA and DVI connectors, We'll discuss in brief in coming articles.


Sound Card - Sound card is a print circuit board which converts the sound into binary codes the native computer language. When we send our sound to the computer with microphone then sound cards convert the sound into codes for processing in computer and after processing then convert the code into sound and send to the speakers as an output. Microphone and Speakers can be attached to sound card so we can record our voice , and play music as well.



Modem - Modems is an abbreviation of MOdulator / DEModulator convert the computer data into information to it through telephone wires from one place to another on the internet. Modem can allow long distance and short distance communication between computers. Usually whenever we fix Modem card into the motherboard and connect the telephone wires then you can get and use the facility of internet.



LAN Card - LAN (Local Area Network) is a such network by which we can connect together many computer and can send/receive data between these connected computers. You can get the advantage to use devices connected to the computer on the network, For example printing on a network computer. You can only able to make this network with the by using LAN card.

LAN card fixed into motherboard. If two computers have LAN card installed in it then you can create a network between these computers. Like Modem, LAN card cannot send/receive information on long-distance.

xii) Peripheral Devices

Peripheral devices are such devices without them computer can work, but are not essential to the computer. Usually, peripheral devices adds a new function to increase the capabilities of computer. Mouse and Keyboard are most essential peripheral devices. But, as input devices these devices are much important to any computer. Normally, peripheral devices connect the computer externally. Some examples of peripheral devices are, Mouse, Keyboard, Printer, Modem, Joystick, etc..

xiii) Ports

For every external device like Mouse, Keyboard, Modem, etc. there is a connection point available from motherboard to get these connected to the computer to send and receive data between computer and devices internally and externally. For example we connect Printer to 'Parallel port' of the computer this port is known as LPT port. We connect modem to serial port which is known as COM port.

xiv) Universal Serial Bus

These are the newly introduced ports and currently the most popular port for connecting any kind of peripheral like Keyboard, Mouse, Printer, Scanner and Camera etc. It's a thin connector, in past there was just one USB port but today new motherboards come with more USB ports with any other port. That's reason why Keyboard/Mouse Serial and PS/2 ports replaced with this powerful port. However If you want to increase number of USB ports you can do this placing card into the expansion slot.

One of the greatest advantage of the USB port is Operating System can able to detect any device attach to USB port automatically without installation of any driver most of the time or ask to install drivers if needed.

Power Supply:

Power supply is source give electric power to the computer. An average Power supply can be 220 volts AC (alternating current) or something that converts our home electricity into 3.3 or 5 volts DC (direct current) for motherboard it's devices and 12 volts DC for hard disk and motors). Today most of average power supplies start from 350 volts AC due to requirement of power from processors, and graphics card, etc..






To Download this article in Urdu version then click below:

Download Chapter 03: Introduction to CPU and it’s Component in Urdu

<<< Back: A Simple Introduction to Output Devices in Urdu >>>

 

 

Please read the remaining parts of lesson 3 by clicking below:

2. How to Use Keyboard Step-by-Step Guide
3. Introduction a Computer Mouse

Read More

How to Use a Computer Mouse - Urdu Guide

Mouse is an input device that is basically a pointing device (Pointing device is a device that controls the cursor which moves around the screen). You can control a mouse with one hand. The computer mouse is use to control the screen with pointing cursor. Let’s talk about how it works.

How Mouse Works?

A standard mouse contains two mouse buttons. The below part of the mouse have smooth surface, and there is a round ball inside the mouse touches the surface that helps to move the cursor on the screen (However, ball mouse are rarely used today because they’re getting useless and stops working a short period of time, however Laser and optical mouse are common now). When you place the mouse on any flat surface or pad and move the mouse on the surface then pointing cursor on the screen also moves. Mouse pointer moves proportionally on the screen when you move the mouse on the flat surface.
Mouse is really an important device when you're drawing on the computer. Remember that, you cannot use mouse in command prompt however mouse is used too often in Windows environment, and without mouse it's hard to operate windows and accomplish tasks. For Example, To get yourself to a button on the screen and to press the button is very easy job with a mouse, but it would be hard or little tricky if you’re going to complete the same task with a keyboard, I’m talking about accessibility options which turns Keyboard Num-pad into a mouse.

We measure mouse speed in CPI (counts per inch) equals to DPI (dots per inch). You can increase or decrease DPI from it’s actual using tricky softwares.

Components of Mouse:

A standard mouse can have two or more buttons. Here we are giving you an example of two button mouse. And again you know that the basic purpose of the mouse is to control interface objects on the screen. Using the mouse is very easy let’s learn how you can use your mouse and what tasks you can perform with a mouse and it's buttons:

Click: When you press a button of mouse, this action is known as 'click'. Usually you can perform the single click with button on the left side of the mouse. With a single click you can select any item on the screen.

Double Click: When you press the left mouse button twice without any break, this action is known as double-click. Usually you open an item with this action.

Right Click: When you press the right side button of the mouse, is known as Right-click. Usually this opens a right click menu of a window.

Drag and Drop:  If you keep pressing the left mouse button and meanwhile you move the cursor and leave the left mouse button is known as 'Drag and Drop'.

Hence, you've understood that mouse and keyboard are basic input devices that sends input data to the computer. After that input data goes to Central Processing Unit (CPU) to process the input data. Next we're going to discuss about Central Processing unit. Let’s keep on reading and learn every basic thing about computer.


To Download this article in Urdu version then click below:

Download Chapter 03: A Simple Introduction to Standard Mouse In Urdu

<<< Next: An Essential Guide to Central Processing Unit Components >>>

Chapter 03 Basic Computer Components ~ Urdu Guide from Muhammad Tayyab Rana

Read More

How to Use Keyboard Step by Step - Urdu Guide

As we all know that keyboard is commonly used input device for computer, now it's the standard for sending textual information, commands and instructions to the computer. However, today we have also touch-input technology, which can help us to do similar functions. We'll discuss these are in the market and who use them. Keyboard is commonly used input device for this purpose, and it's most recommended to these types of essential tasks.
Now let's talk about the basic components of the keyboards, so you can understand that what you can do with your keyboard.

 

Let’s Start Exploring Your Keyboard!

 

1) Insert or Delete Alphabet/Numeric Characters:

1. In keyboard, there are a group of Alphabetic keys from 'A' to 'Z'. After these keys at bottom there is a spacebar button.

2. Above Alphabetic keys, there are Numeric keys in a row from '0' to '9'. These numeric keys have some symbolic keys as well that we mostly use every(@, #, ^, and $).

3. You can see a group of keys like a calculator at the right side of the keyboard which known as 'Numeric keypad'. We use this to insert numeric characters. There is also a 'Num Lock' at the right corner of the keypad which is a toggle button (on/off button). When you turn on Num Lock key, you can type numeric characters and when turned off can be used to as cursor control keys/or a mouse pointer.

4. At very right of the numeric keys you'll backspace button, which used to delete one character to the left.

(Tip: Press Ctrl+Backspace to delete one word to the left).

5. Delete Key usually located on the Cursor-control key, the purpose of this key is to delete single character from right side each time and this continues whenever you press Delete key.

6. Ins or Insert key is a toggle key located near cursor-control keys. Generally, When this key is turned on, and you started to type between characters' type already, then it automatically creates space new between these existing characters. However, if you turn off this key, newly typed character will replace with the previously inserted characters. This operation is known as 'Overwriting'.

 

While Typing you always see a black blinking vertical bar which moves towards right, it's commonly known as 'cursor', we also call it the insertion point.ack vertical bar blinking and moving towards right when you type, it usually known as 'cursor'. We also call it insertion point.

 

2) Perform Variety of Task By Applying Function Keys & Shortcut Keys

1. There are two Enter keys in the keyboard, which used to confirm any operation.

2. In very old days, there were two known types of Keyboard 'Enhanced' and 'Non-Enhanced' categorized based on the number of keys in keyboard. Nowadays, Enhanced keyboard is the standard which also contains 12 function keys, which are located above the numeric keys. The main purpose of these keys is to perform specific tasks. At very left of function keys there is an 'Escape' or 'Esc' key, which used to end or quit running operation.

3. A Keyboard has six modifier keys, two Ctrl or Control Keys, Two Alt or Alternate Keys and two Shift keys. These keys are often used to apply shortcut keys.

4. You can use Shift key to change the letter case to lower or capital-case. Suppose if you're typing alphabets and press Shift and C simultaneously, then letter case will change to capital-case. Basically, Shift key does the reverse any task. There is a Caps Lock key which is a toggle key (on/off key). When it's turned on you can type the alphabet letters in Capital-case.

5. Nowadays, keyboard is included with Windows Key by which you can apply shortcut keys that are associated with this key. For example, if you just press Windows Key it opens the Start Menu.

 

3) Navigate Around Items or Objects:

1. Keyboard has a 'Tab' key. This key is used to insert tabulation and also use to move from one object to another in the Operating system's Interface.

2. Keyboard has 8 or more Cursor Control keys. The first four keys are ↑Up, ↓Down, ←Left and →Right. A Home key (Which take the cursor to initial location of any object/item). an End key (Which take the cursor to last location of any object/item). A Page Up or Pg Up key(which take the cursor to one page above of the information currently showing) and a Page Down or Pg Dn key (which take the cursor to one page bottom of the information currently showing).You can also see these keys in numeric keypad, if you turn off Num lock key.

 

4) Some More Important Keys You Need to Know:

3. A Scroll Lock or Scr lk key in Keyboard used to lock scrolling function, which located near Print screen key.

4. There is Print Screen or Prnt Scn key, captures the screenshot of the currently displayed items/objects in the screen and copies the captured screen to Clipboard (will discuss later).

5. If you want to stop a running process temporarily, then you can press Pause/Break key.

6. A standard keyboard has also included with a Right-click Context Menu key opens the menu when use press presses the Right-click button.

 

This is all in the keyboard you have it in your home or office, office. I'm sure that an average person knows all these things, because if you work in the program like Microsoft Word, Excel then you'll play with all these keys and shortcuts.

 

Let’s Play the Game!

Now let’s play this game with me by writing comments with the ‘name’ of the key or the group of keys that I marked with a number.

 

To Download this article in Urdu version then click below:

Download Chapter 03: How to Use Keyboard Device Step by Step in Urdu

<<< Next: A Simple Introduction to Standard Mouse in Urdu >>>

 

Please read the remaining parts of lesson 3 by clicking below:

2. Introduction a Computer Mouse
3. An Essential Guide to CPU

Read More

Computer Keyboard, Is Like a Typewriter???...

Keyboard is the most commonly used input device for computer systems. It has derived from the old typewriter. But it's not actually like a typewriter, however both have many same keys which do similar function like pressing a key and character prints. In general, as a standard way to interacting with computer system, a Keyboard actually used to execute commands not only for typing characters.

 

 

A Keyboard a keypad device which consists of keys/buttons that user can press to print character or executing commands. When a user presses it process in this way:

* Keyboard controller detects this keystroke

* Places a scan code in the keyboard buffer that indicates which key is pressed

* These scan codes go through the operating system

* Finally CPU accepts it to print on the screen

These scan codes processes in the form of ASCII codes(American Standard Code for Information Interchange).

 

On the basis of keys and their functions a keyboard is different than typewriter. It has similar keys for typing characters but some additional keys for navigation, numeric keypad and function keys. These keys mainly used to accomplishing of commands pressed by the user.

 

In later post, we’ll discuss how keyboards key function, and how a user can use them to fulfill their working purposes.

Read More

Introduction to Input & Output Devices - Just like fun

As we know that Computer process information in three steps:

 

1) Inputting data to Computer through input devices (Keyboard, Mouse)
2) Processing data inputs in Central Processing Unit (CPU)
3) Show processed data to output devices (Monitor Screen)

 

 

 

 

As everybody knows that today computers have too many input and output devices. So, It's not enough tell all about them and their functions in one piece of information. That's why we're going to discuss them one by one in a fun like way.

 

At first, Keyboard or Mouse are commonly the basic way to interacting with your computer. But do you know input devices aren't just bound to keyboard & mouse, So what's another???.. , if you've money you can buy any sort of input device for your own purposes which are available in the market. An input device could be a microphone, scanner, card reader, etc. All input devices are use to make your work possible to do, easy and faster that you can't imagined do it by yourself with your computer.

 

At second, similar case for output devices, in which Monitor is very commonly used output device. Without it you can't see what input you have given to the CPU. If someone has damaged your monitor so you must've to worry about to get another one huh,  What it means if the computer without monitor, yes!!!… a man without head oh wow you guessed it, you're a genius.  As like, input devices there are many output devices are available on the basis of purpose of your work. Such as, if you want a hard copy of your college notes you need a printer. If you don't have money to buy it, then just go to your near printing shop for your needs, and have a fun.

 

It’s all from today, Just little fun & little info. In later posts, we'll discuss about input, output devices more briefly and seriously. So, go ahead and comment below to tell me what’s wrong with it.

 

 

To Download this article in Urdu version then click below:

Download Chapter 03: Input & Output Components of Computer System

 

 

<<< Next: How to Use Keyboard Step by Step >>>

 

Please read the remaining parts of lesson 3 by clicking below:

2. How to Use Keyboard Step-by-Step Guide
3. Introduction a Computer Mouse
4. An Essential Guide to CPU

Read More