Introduction to Computers

Computing Fundamental

Introduction to Computer

 Computer:-

What is Computer?

A computer is an electronic device that manipulates information, or data. It has the ability to store, retrieve, and process data. You can use a computer to type documents, send email, and browse the Web. You can also use it to handle spreadsheets, accounting, database management, presentations, games, and more.

Computers Simplified:-

For beginner computer users, the computer being manufactured at an electronics store can be quite a mystery, not to mention overwhelming. However, computers really aren't that mysterious. All types of computers consist of two basic parts:

Hardware is any part of your computer that has a physical structure, such as the computer monitor or keyboard.

Software is any set of instructions that tells the hardware what to do. It is what guides the hardware and tells it how to accomplish each task. Some examples of software include web browsers, games, and word processors such as Microsoft Word.

Anything you buy for your computer can be classified as either hardware or software. Once you learn more about these items, computers are actually very straightforward.

The first electronic computer, the Electronic Numerical Integrator and Computer (ENIAC), was developed in 1946. It took up 1,800 square feet and weighed 30 tons.

What are different types of computers?

When most people hear the word "computer," they think of a personal computer such as a desktop or laptop computer. However, computers come in many shapes and sizes, and they perform many different functions in our daily lives. When you withdraw cash from an ATM, scan groceries at the store, or use a calculator, you're using a type of computer. Desktop Computers:-

Many people use desktop computers at work, home, school, or the library. They can be small, medium, or large in style, and they usually sit on a desk. Once you add a monitor, mouse, and keyboard, you have what is typically known as a desktop computer.

Most desktop computers are easy to upgrade and expand or add new parts. Another benefit of desktop computers is the cost. If you compare a desktop and a laptop with the same features, you will most likely find that the desktop computer is priced lower.

Laptop Computers:-

The second type of computer you may be familiar with is a laptop computer, or a laptop. Laptops are battery- or AC-powered personal computers that are more portable than desktop computers, allowing you to use them almost anywhere.

Because a laptop is smaller than a desktop, it's more difficult to access its internal components. This means you may not be able to upgrade them as easily as a desktop. However, it's usually possible to add more RAM or a larger hard drive.

A laptop computer is sometimes called a notebook computer because of its size.

Servers:-

A server is a computer that "serves up" information to other computers on a network. Many businesses have file servers that employees can use to store and share files. A server can look like a regular desktop computer, or it can be much larger.

Servers also play an important role in making the Internet work: They are where webpages are stored. When you use your browser to click a link, a web server delivers the page you requested.

Other Types of Computer:-

Today, there are many everyday devices that are basically specialized computers, even though we don't always think of them as computers. Here are a few common examples:

•       Tablet computers: These use a touch-sensitive screen for typing and navigation. Because they don't require a keyboard or mouse, tablet computers are even more portable than laptops. The iPad is an example of a tablet computer.

•       Mobile phones: Many mobile phones can do a lot of things computers can do, such as browsing the Internet and playing games. These phones are often called smartphones.

PCs and Macs:-

Personal computers come in two main styles: PC and Mac. Both styles are fully functional, but they do have a different look and feel, and many people prefer one or the other.

PC: This type of computer began with the original IBM PC that was introduced in 1981. Other companies began to create similar computers, which were called IBM PC Compatible (often shortened to PC). Today, this is the most common type of personal computer, and it typically includes the Microsoft Windows operating system.

Mac: The Macintosh computer was introduced in 1984, and it was the first widely sold personal computer with a Graphical User Interface, or GUI (pronounced gooey). All Macs are made by one company, Apple Inc., and they almost always use the Mac OS X operating system.

Although PC can refer to an IBM PC Compatible, the term can also be used to refer to any personal computer, including Macs.

In this manual, we'll mostly be focusing on PCs and the Windows operating system. If you're using a Mac, you may notice some differences with the way your computer works. However, much of the information in this tutorial will still apply, no matter which type of computer you're using.

Operating Systems:-

What is Operating Systems?

An operating system is the most important software that runs on a computer. It manages the computer's memory, processes, and all of its software and hardware. It also allows you to communicate with the computer without knowing how to speak the computer's "language." Without an operating system, a computer is useless.

The Operating System’s Job:-

You've probably heard the phrase boot your computer, but do you know what that means? Booting is the process that occurs when you press the power button to turn your computer on. During this process (which may take a minute or two), the computer does several things:

•       It runs tests to make sure everything is working correctly.

•       It checks for new hardware.

•       It then starts up the operating system.

In the image below, you can see the start-up screen that appears when you turn on a Windows 7 computer.

Once the operating system has started up, it manages all of the software and hardware on the computer. Most of the time, there are many different programs running at the same time, and they all need to access your computer's central processing unit (CPU), memory, and storage. The operating system coordinates all of this to make sure each program gets what it needs. Without the operating system, the software wouldn't even be able to talk to the hardware, and the computer would be useless. In the image below, you can see how Windows 7 appears after starting up.

Types of Operating Systems:-

Operating systems usually come preloaded on any computer you buy. Most people use the operating system that comes with their computer, but it is possible to upgrade or even change operating systems.

The three most common operating systems for personal computers are Microsoft Windows, Mac OS X, and Linux.

Modern operating systems use a Graphical User Interface, or GUI (pronounced "gooey"). A GUI lets you use your mouse to click on icons, buttons, and menus, and everything is clearly displayed on the screen using a combination of graphics and text.

Each operating system's GUI has a different look and feel, so if you switch to a different operating system it may seem unfamiliar at first. However, modern operating systems are designed to be easy to use, and most of the basic principles are the same.

In the images below, you can see the Windows and Mac OS X GUIs.

Before GUIs, computers had a command-line interface, which meant the user had to type every single command, and the computer would only display text.

Microsoft Windows:-

Microsoft created the Windows operating system in the mid-1980s. Over the years, there have been many different versions of Windows, but the most recent ones are Windows 8 (released in 2012), Windows 7 (2009), and Windows Vista (2007). Windows comes preloaded on most new PCs, which helps to make it the most popular operating system in the world. If you're buying a new computer or upgrading to a newer version of Windows, you can choose from several different editions of Windows, such as Home Premium, Professional, and Ultimate. You may need to do some research to decide which edition is right for you.

Apple MAC OS X:-

Mac OS is a line of operating systems created by Apple Inc. It comes preloaded on all new

Macintosh computers, or Macs. All of the recent versions are known as OS X (pronounced O-

S       Ten),      and      the       specific       versions       include       Yosemite       (released       in

2014), Mavericks (2013), Mountain Lion (2012), Lion (2011), and Snow Leopard (2009). Apple also offers a version called Mac OS X Server, which is designed to be run on servers.

According to Global Statistics, Mac OS X users account for 7.5% of the operating systems market as of January 2013—much lower than the percentage of Windows users (more than 90%). One reason for this is that Apple computers tend to be more expensive. However, many people prefer the look and feel of Mac OS X.

Linux:-

Linux (pronounced LINN-ux) is a family of open-source operating systems, which means they can be modified and distributed by anyone around the world. This is different from proprietary software like Windows, which can only be modified by the company that owns it (Microsoft). The advantages of Linux are that it is free, and there are many different distributions (or versions) you can choose from. Each distribution has a different look and feel, and the most popular ones include Ubuntu, Mint, and Fedora.

Linux is named after Linus Torvalds, who created the Linux kernel in 1991. The kernel is the computer code that is the central part of an operating system.

According to Global Statistics, Linux users account for less than 1% of the operating systems market as of January 2013. However, most servers run Linux because it's relatively easy to customize.

Operating Systems for Mobile Devices:-

The      operating         systems            we've   been     talking             about   were    designed          to         run on desktop or laptop computers. Mobile devices such as phones, tablet computers, and mp3 players are different from desktop and laptop computers, so they run operating systems that are designed specifically for mobile devices. Examples of mobile operating systems include Apple iOS, Windows Phone, and Google Android.

Operating systems for mobile devices generally aren't as fully featured as those made for desktop or laptop computers, and they aren't able to run all of the same software. However, you can still do a lot of things with them, like watch movies, browse the Web, manage your calendar, and play games.

Understanding Applications:-

You may have heard people talking about using an application, or an app. But what exactly does that mean? An app is a type of software that allows you to perform specific tasks. Applications for desktop or laptop computers are sometimes called desktop applications, and those for mobile devices are called mobile apps. When you open an application, it runs inside the operating system until you close it. Much of the time, you will have more than one application open at the same time, and this is known as multitasking.

App is a common term for an application, especially for simple applications that can be downloaded cheaply or even for free. Many apps are also available for mobile devices and even some TVs. Types of Desktop Applications:-

There are countless desktop applications out there, and they fall into many different categories. Some are more full-featured (like Microsoft Word), while others may only do one or two things (like gadgets). Below are just a few types of applications you might use:

Word processors: A word processor allows you to write a letter, design a flyer, and create many other kinds of documents. The most well-known word processor is Microsoft Word.

Personal finance: Personal finance software, such as Quicken, allows you to keep track of your income and expenses, create a budget, and more. Most personal finance programs can automatically download information from your bank so you don't have to manually add your transactions.

Web browsers: A web browser is the tool you use to access the Web. Most computers come with a web browser pre-installed, but you can also download a different one if you prefer. Examples of browsers include Internet Explorer, Firefox, Google Chrome, and Safari.

Games: There are many different games you can play on your computer. They range from card games such as Solitaire to action games like Halo 2. Many action games require a lot of computing power, so they may not work unless you have a newer computer.

Media players: If you want to listen to MP3s or watch movies you've downloaded, you'll need to use a media player. Windows Media Player and iTunes are popular media players.

Gadgets: Sometimes called widgets, these are simple applications you can place on your desktop (or on the Dashboard if you're using a Mac). There are many different types of gadgets, and they include calendars, calculators, maps, and news headlines.

Installing Desktop Applications:-

In order to work, an application usually has to be installed on your computer. Typically, installation is as simple as inserting the installation disc and following the instructions on the screen. For software downloaded from the Internet, you can usually double-click it after it is finished downloading and then follow the instructions on the screen. Many applications include a readme file (for example, readme.txt), which includes installation instructions and other information. Opening Files with Applications:-

Many applications are designed to open one or more types of files (or file formats). For example, Microsoft Word can create and edit Word documents. If you don't have the right kind of application, you won't be able to open a file. For example, if you are using Access 2010, you will need to have Microsoft Access in order to open the sample database.

There are two main ways to open a file:

Find the file on your computer, and double-click it. This will open the file using the default program.

Open the application, then use the application to open the file. Once the application is open, you can go to the File menu at the top of the screen and select Open. This is useful because some files can be opened by several different applications, and this method allows you to choose which application to use.

If you're not sure what a file's format is, you can look at the extension at the end of the file name (for example .docx, .txt, or .jpg). On some computers, the extension may be hidden, and you may need to look at the icon to determine the file format.

Mobile Apps:-

Desktop and laptop computers aren't the only devices that can run apps. You can also download apps for mobile devices like smartphones and tablet computers, which opens up a lot of new possibilities. Here are a few examples of mobile apps:

RedLaser: You can use RedLaser to compare prices while shopping. You simply scan an item's barcode using your phone's built-in camera, and the app searches the Web for the best price.

Word Lens: Word Lens is a language translator app. Like RedLaser, it uses your phone's camera to take a picture of a sign, menu, or other text you want to translate, and it displays the translation for you.

Foursquare: If you're going out to a restaurant, bar, or mall, you can "check in" with

Foursquare to find nearby friends and also let your friends know where you are. Foursquare can also show you a list of nearby businesses (using your phone's built-in GPS), which can help you discover places you've never been to before.

Compared with traditional applications, mobile apps are relatively cheap. Many of them cost as little as $0.99, and others are free. If your mobile device has an Internet connection, you can download apps directly onto the mobile device. Otherwise, you can download them to your computer and then transfer them over.

Web Applications and the Cloud:-

You may have heard people using terms like the cloud, cloud computing, or cloud storage. But what exactly is the cloud? Basically, the cloud is the Internet—more specifically, it's all of the things you can access remotely over the Internet. When something is in the cloud, it means it's stored on servers on the Internet instead of on your computer. It lets you access your calendar, email, files, and more from any computer with an Internet connection.

If you've ever used web-based email, then you've used the cloud—all of the emails in your inbox are stored on servers. However, there are many other services that use the cloud in different ways. Here are just a few examples:

•       Dropbox is a cloud storage service that lets you easily store and share files with other people, and it lets you access your files from a mobile device as well.

•       Evernote lets you type notes, clip webpages, take photos, and organize all of them from your computer or mobile device.

•       Mozy and Carbonite can automatically back up your data in case your computer is lost, stolen, or damaged. Why use the Cloud?

There are many reasons to use the cloud, but the main reasons are convenience and reliability. In the past, if you wanted to bring a file with you, you would have to save it to a USB flash drive, external hard drive, or CD-R disc. Saving a file to the cloud ensures that you'll be able to access it with any computer that has an Internet connection, so you don't have any physical media to keep track of. The cloud also makes it much easier to share a file with co-workers or friends, making it possible to collaborate over the Web.

With the cloud, you're much less likely to lose your data because it is stored on servers. However, just like anything online, there is always a risk that someone may try to gain access to your personal data, so it's important to choose a strong password and pay attention to any privacy settings for the service you're using.

What is a Web App?

Previously, we talked about how desktop applications allow you to perform tasks on your computer. However, there are also web applications (or web apps), which run in the cloud and do not need to be installed on your computer. These are sometimes called cloud apps.

Example of Web Apps:-

Here are a few examples of web apps:

Online email services: Services like Gmail and Yahoo! Mail run within your browser and can do many of the same things email programs like Microsoft Outlook can do. After you sign up for an online email service, you can begin using it immediately—no installation is required. Instead of being stored on your computer, your emails are stored in the cloud.

Google Docs: Google Docs is an office suite that runs within your browser. Much like Microsoft Office, you can use it to create documents, spreadsheets, presentations, and more. Your documents are stored in the cloud, which makes it easy to share them with other people.

Facebook: Facebook lets you create an online profile and interact with your friends. Profiles and conversations are constantly evolving, so Facebook uses web app technologies throughout the site to keep the information up-to-date. There are also games and other web apps you can add to your Facebook profile.

Web apps are becoming more and more integrated with websites, and it may be difficult to distinguish between a web application and a "regular" website. In many cases, you may be using a web application without even knowing it!

How do Web App works?

When you use a web app, you are working from your computer or mobile device, but much of the actual processing is done by a network of servers. These servers can pool all of their processing power in order to handle requests from all over the world. They also use specialized servers to store the data you're working with, as well as the data from all other users. All of this happens very seamlessly, so it looks almost like the application is running on your computer.

For example, if you open a document with Google Docs, your web browser will communicate with the network of servers to display your document. As you edit the document, your browser will work closely with the servers to make sure everything is kept up-to-date.

                    Inside the Computer 

 

The objectives of this session are:-

1.      To identify the components of a computer system.

2.      To be able to identify the components inside the CPU of the computer.

3.      To be able to define the purpose of each component of the CPU of the computer.

4.      To be able to identify the components of Motherboard.

Components of a Computer:-

The Components of a computer can be categorized into:

1.      Input Devices.

2.      Output Devices.

3.      Storage Devices.

We have talked about Input devices, output devices and storage devices in our previous sessions. We will name these components here just to recall them.

Input Devices are the one which are used to give input to the computer e.g. Keyboard, Mouse etc.

  Output Devices are the one which are used to display the output to the user e.g. Monitor, printer etc.

  Storage Devices are the one which are used to store data temporarily or permanently e.g. Hard Disk, RAM, ROM etc.

Computer System with its components looks like: 

CPU stands for Central Processing Unit. It is the major component of the computer which is having all the components of the computer placed in it.

The Computer Casing without components placed in it looks like: 

The most important component of the CPU is the motherboard of the computer. Everything in the PC directly or indirectly plugs into the motherboard. A properly configured and functioning motherboard provides a solid foundation for all the other hardware in the system. The converse of this statement is equally true. No PC with a poorly configured or poorly functioning motherboard will ever be stable, solid, or dependable.

In this session, you will learn how motherboards work to unite all of the different system components into one harmonious system. You will learn to identify the parts that make up a motherboard and to identify the various motherboards you may run into out in the real world. You will also learn how to install a motherboard in a system. So roll up your sleeves and prepare

to meet the component that binds the whole system together: the motherboard. 

 

The motherboard is like a big city with many streets and highways that connect all of the buildings together. Instead of streets and highways, the motherboard uses tiny electrical paths to connect each component of the computer together. These paths are called "buses." The more buses that connect to a component, the faster it can operate. Larger buses are able to operate faster than smaller buses. Buses work just like highways. Wider highways and highways with more lanes are able to carry more traffic than smaller highways and highways with less lanes. Many cities have a freeway. A freeway is designed so that large amounts of traffic can move quickly from one place to another. The motherboard also has a "freeway." It is called the "front side bus," (or FSB). It is the most important bus on the motherboard, because it connects the processor to the main memory and the Northbridge chipset. The faster the FSB is, the faster the computer can operate, since the processor is constantly using the main memory to store and retrieve information. Sometimes the FSB is also called the "system bus." Below is a diagram showing the front side bus in red. Keep in mind that on an actual motherboard, each line representing the buses would actually consist of many electrical paths instead of just one. 

 

Like a traffic cop, the Chipset, (2 chips on this motherboard), manages and directs the flow of data between each of the components.

Let us discuss the components of motherboard one by one:

1. 20 Pin ATX Power Connector:-

A motherboard would be nothing without power going to it. There must be a connection between the outlet in your wall and the CPU and other components of your computer. On an ATX motherboard, this connection is through the power connector. 

2. DRAM Memory Slots:-

Motherboards have two, three, or four black slots near the CPU for memory. These are called memory slots generically, although techs know that they’re called DIMM slots for 168-pin SDRAM and 184-pin DDR SDRAM DIMMs, and RIMM slots for 184-pin RDRAM sticks. The slots have latches on each side to keep the DIMM or RIMM from coming loose. 

 

3. IDE connector(Integrated Drive Electronics):- 

 This connector is use to connect the IDE cable of the HDD (Hard Disk Drive) or  CD/DVD ROM to the Motherboard IDE. Both EIDE and FDD ports are keyed, with a  notch in the middle of the port. This prevents you from inserting the IDE  cables  incorrectly.

4. Chipsets:-

The two chipset chips facilitate communication between the CPU and other devices in the system and so are relatively centrally located on the motherboard. 

North Bridge IC is a passion name as being north of the PCI buses or the PCI slots of the motherboard. The true name of the north bridge is MCI or Memory Controller Hub. Assigned to manage and control the computer memory before the processing of the CPU chip.

South Bridge IC is a passion name as being south of the PCI buses or PCI slots. The true name of the south bridge is I/O Controller HUB (ICH).It is a type of microchip task to control all the Input and output devices of the computer. Such as the keyboard and mouse. And the monitor screen of the computer that commonly found at the rear back of the CPU or system unit. 

 

 

 

5. Expansion Slots

You should have noticed a bank of similar slots sitting near one side of your motherboard. Those are part of the expansion bus. One of the early strengths of the IBMcompatible PC was its recognition that not everyone wanted the exact same computer. Rather than including every possible option as a part of the motherboard, the PC’s designers allowed you to customize your computer by adding components through the expansion slots.

This turned out to be a wonderful idea, particularly because expansion options such as sound and video tend to change more quickly than CPUs. Expansion slots allow the user to increase the capabilities of a computer without having to buy an entire new system every time an innovation appears.

Motherboards have one medium-sized brown slot next to some number of white slots usually five, but the number can be anywhere from one to six and possibly a much smaller brown slot. These are the AGP, PCI, and CNR expansion slots, respectively.

 The Accelerated Graphics Port (AGP) slots provide exclusive 32-bit, 66 MHz  connections for video cards. AGP slots always sit closer to the Northbridge than  any  other expansion slot

 Peripheral Component Interconnect (PCI) slots are general-purpose, 32-bit, 33-MHz  slots you will see a wide variety of expansion cards in these slots, which are designed to  enable quick communication between internal hardware add-ons and the CPU.

 Communication and Networking Riser (CNR) slots, on the other hand, are not nearly  as common as PCI slots and are used only for network cards and modems, devices that  enable you to connect a computer to the Internet and to smaller networks. Figure below  shows both the white PCI slots and the small, brown CNR slot. 

 

6. CPU Socket:-

Although clearly central to any PC, the CPU doesn’t sit anywhere near the center of an ATX motherboard. The CPU inserts into the motherboard near one corner, on the opposite end from the expansion slots.

 

. CMOS/BIOS BATTERY- 

In this part, the CMOS/BIOS battery is hold, so that it can provide 3 volts direct current/voltage to the CMOS IC. To preserve the BIOS settings of the computer. Such as the time module, hardware information and settings/parameter, etc. 

CMOS Complementary Metal Oxide Semiconductor

BIOS- Basic Input/Output system. Is a set of a program stored in CMOS IC, use to preserve the BIOS configuration of the computer.

CMOS BATTERY PART NUMBER- lithium dry cell CR 2032 3 volts.

8. Connectors for Integrated Peripherals:-

I/O ports:- This is located in the rear panel of the CPU, this use to connect the outside hardware or peripherals of the computer.

 PS/2 ports- these are use to connect the mouse(green color)and the  keyboard(purple color)

 DB 25 female connector (printer port)-this is use to connect the impact printer,  one of that the DOT MATRIX printer, ex. the Epson LX 300+.

            DB 9 male connector (Serial or com1 port)-this use to connect a serial device of              the computer, such as the serial mouse and external modem.

 VGA port(built-in)- this is use to interface the DB cord of the monitor screen or  to connect the monitor screen of the computer. The fastest video card versions are  base on the standard of the vga slots, ex: the AGP and PCI’e card.

 USB 2.0 × 2 ports- these are the ports of the usb devices of the computer.  Attached externally of the system unit,one of that is the USB flash drive. As of  now the versions or speed of the USB are the 1.0 and 2.0 compatible.

             LAN port- this called as Local Area Network of the computer. This is       use to connect the numbers of node or work stations (PC) to form a local area network               of the computer with in their area. Using the type of communication media such          as the network switch and router.

  Audio Port- this is use to connect the speaker, mic, and MIDI (Musical     Instrument Digital Interface) device of the computer. 

 

That is how to assemble a PC which you use at home or offices! I hope now you can assemble a PC yourself!