COMPUTER BASIC

Computers Simplified

For beginning computer users, the computer aisles 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 are web browsers, games, and word processors such as Microsoft Word.

A motherboard (hardware)

Microsoft Word (software)

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 the 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

A desktop computer

Many people use desktop computers at work, home, school, or the library. They can be small, medium, or large in style, and usually sit on a desk. Once you add a monitor, mouse, and a 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.

Some desktop computers have a built-in monitor to save space. These are often called all-in-one desktop computers.

Laptop Computers

A laptop computer

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

Since a laptop is smaller than a desktop, it's more difficult to access the internal components. That means you may not be able to upgrade them as much as a desktop. However, it's usually possible to add more RAM or a bigger hard drive.

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

Servers

A server room

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 web pages are stored. When you use your browser to click a link, a web server delivers the page you requested.

Other Types of Computers

Today, there are many different types of computers that you can buy, and some of them are even more portable than laptops. Here are a few common examples:

The iPad, a type of tablet computer

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

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.

A PC

A Mac

• 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.

Challenge!

• Think about the activities you perform or want to perform using a computer (email, online shopping, etc.).
• Think about all the computers that are necessary for you to complete your day-to-day activities.
  • Is it a computer that controls the stoplights so you can drive to work?
  • How did the cashier scan and calculate your grocery items?
  • Does the coffee store you visit use a computer to order their inventory?
  • Is the weather map on television computer-generated?

  • What is an application?

    Applications displayed in the Launchpad in OS X Lion

    You may have heard people talking about using an application or an app. But what exactly does that mean? An application (or 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 very common slang 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 that you might use:

    Microsoft Word
    • 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 type in all of your transactions.
    • Web Browsers: A web browser is the tool that you use to access the World Wide 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 that 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.

    

    Add caption

    Watching a movie in Windows Media Player
    • Media Players: If you want to listen to mp3s or watch movies that 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 that 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, news headlines, and more.

    • 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 that is 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.

      Use caution when downloading software, as it can contain viruses or other malware. If you have an antivirus program, you should scan the downloaded software before installing it. For more information, check out Protecting Your Computer from Internet Threats in our Internet Safety tutorial.

      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 taking our Access 2010 tutorial, 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.
      Double-clicking a file to open it
      • 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.
      Opening a file within Microsoft Word

      1. 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

         

         Add caption

         An iPhone running a mobile app

         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 that you want to translate, and then 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 that you've never been to before.

         Compared to traditional applications, mobile apps are relatively cheap. Many of them cost as little as 99 cents, 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.
         

         Some of the tutorials on GCFLearnFree.org are available as mobile apps. You can go to our Mobile Apps page to download them for free.

         Introduction

         

         Add caption

         Watch the video (2:12). Need help?

         The basic parts of a desktop computer are the computer case, monitor, keyboard, mouse, and power cord. Each part plays an important role whenever you use a computer.
         

         Watch the video to learn about the basic parts of a desktop computer.

         Computer Case

         A computer case

         The computer case is the metal and plastic box that contains the main components of the computer. It houses the motherboard, central processing unit (CPU), the power supply, and more.
         Computer cases come in different shapes and sizes. A desktop case lies flat on a desk, and the monitor usually sits on top of it. A tower case is tall and sits next to the monitor or on the floor. The front of the case usually has an on/off switch and one or more optical drives.
         

         Most of the personal computers you can purchase today include tower cases, rather than desktop cases; however, some computers are being made with all of the internal components built into the monitor, which completely eliminates the tower.

         An all-in-one iMac
       

      Monitor

      A monitor
      The monitor works with a video card, located inside the computer case, to display images and text on the screen. Newer monitors usually have LCD (liquid crystal display) or LED (light-emitting diode) displays. These can be made very thin, and they are often called flat panel displays. Older monitors use CRT (cathode ray tube) displays. CRT monitors are much bigger and heavier, and they take up more desk space.
      Most monitors have control buttons that allow you to change your monitor's display settings, and some monitors also have built-in speakers.
      
      LED displays are actually LCD displays that are backlit with light-emitting diodes. This allows for greater contrast than a traditional LCD display.

      Power Cord

      A power cord connected to a surge protector
      The power cord is the link between the power outlet and the power supply unit in the computer casing. If the power cord is not plugged in, the computer will not power on. To protect your computer from voltage spikes, you can plug the power cord into a surge protector. You can also use an Uninterruptable Power Supply (UPS), which acts as a surge protector and also provides temporary power if there is a blackout.
      

      Keyboard

      The keyboard is one of the primary ways we communicate with the computer and enter data. There are many different types of computer keyboards such as wired, wireless, ergonomic, multimedia, and more. Although there may be differences in the location of some keys or features, keyboards are very similar and allow you to accomplish basically the same tasks.
      

      Review the interactive below to learn about the different parts of the keyboard.

      
      

      If you want to improve your typing skills, check out our blog article 5 Free Sites for Learning How to Type.

      Mouse

      A mouse

      The mouse is a peripheral that is known as a pointing device. It lets you point to objects on the screen, click on them, and move them.
      There are two main types of mice: optical and mechanical. The optical mouse uses an electronic eye to detect movement and is easier to clean. The mechanical mouse uses a rolling ball to detect movement. Generally, a mechanical mouse is cheaper, although it may require regular cleaning to keep it working properly.
      Traditionally, a mouse connects to the computer using a USB or PS/2 connection. However, you can also buy a wireless mouse, which can reduce clutter on your desktop.
      

      Mouse Alternatives

      There are other devices that can do the same thing a mouse can do, but with a different look and feel. Many people find them to be easier to use, and they also require less desk space than a mouse. The most common mouse alternatives include:
      

      A touchpad on a laptop
      • Trackball: A trackball has a ball on top that can rotate freely. Instead of moving the device like a mouse, you can simply roll the ball with your fingers to move the pointer. Some mobile devices have miniature trackballs that can be controlled with your thumb.
      • Touchpad: A touchpad (also called a trackpad) is a touch-sensitive pad that lets you control the pointer by making a "drawing" motion with your finger. Touchpads are very common on laptop computers.

        Challenge!

        • Think about the desktop computers you've seen at work, school, the library, a store, or a friend's house. What did they look like? Were they all-in-one, or did they have a separate tower?
        • Review the Parts of the Keyboard interactive on page 3 of this lesson. Are there any keys that you haven't used before?
        • If you're using a mouse, flip it over to see whether it's optical or mechanical.
        • Is your monitor LCD, LED, or CRT?
        • If your monitor has control buttons, try adjusting the brightness and contrast.
     

http://www.gcflearnfree.org/computerbasics/15