Introduction to Computer

 What is a computer?

A computer is an electronic device that manipulates, or data. It has the ability to store, retrieve, and process data. You may already know that you can use a computer to type documents, sends email, play games, and browse the web. You also use it to edit or create spreadsheets, presentations, and even videos.

Hardware VS Software

Before we talk about different types of computers, let’s talk about two things all computers have in common: hardware and software.

▶ Hardware is any part of your computer that has physical structure, such as the keyboard or mouse. It also includes all of the computer’s internal parts, which you can see in the image below.

▶ Software is any set of instructions that tells the hardware what to do and how to do it. Examples of software include web browsers, games, and word processor.

Everything you do on your computer will rely on both hardware and software. For example, right now you may be viewing this lesson in a web browser (software) and using your mouse (hardware) to click from page to page. As you learn about different types of computers, ask yourself about the differences in their hardware.

You will see the different types of computers also often use different types of software.

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. However, computers computer 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 stores, or use a calculator, you are using a types of computer.

Desktop computers

Many people use desktop computers at work, home, and school. Desktop computers are designed to be placed on a desk, and they’re typically made up of a few different parts, including the computer case, monitor, keyboard, and mouse.

Laptop computers

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

Tablet computers

Tablet computers are handheld computers that are even more portable than laptops. Instead of a keyboard and mouse, tablets use a touch-sensitive screen for typing and navigation. The iPad is an example of a tablet.

Servers

A server is computer that serves up information to other computers on a network. For example, whenever you us the internet, you are looking at something that’s stored on a server on a server. Many business also use local files servers to store and share files internally.

Other types of computers

Many of today’s electronic are basically specialized computers, though we don’t always think of them that way. Here are a few common examples.

  §  Smartphones: Many cell phones can do a lot of things computers can do, including browsing the internet and playing games. They are often called smartphones.

  §  Wearable: Wearable technology is a general term for a group of devices including fitness trackers and smart watches that are designed to be worn throughout the day. These devices are often called wearable for short.

  §  Game consoles: A game console is a specialized type of computer that is used for playing video games on your TV.

  §  TVs: Many TVs now include applications or apps that let you access various types of online content. For example, you can stream videos from Internet directly onto your TV.

PCs and Macs

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

PCs

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

Macs

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

Basics Parts of a Computer

The basic part 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.

Computer Case

The computer case is the metal and plastic box that contains the main components of the computer, including the motherboard, central processing unit (CPU), and power supply. The front of the case usually has On/Off button and one or more optical drives.

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. All-in-one computers come with the internal components built into the monitor, which eliminates the need for a separate case.

Monitor

The monitor works with a video card, located inside the computer case, to display images and text on the screen. Most monitors have control buttons that allows you to change your monitor’s display settings, and some monitors also have built in speakers.

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 rays tube) displays. CRT monitors are much larger and heavier, and they take up more desk space.

Keyboard

The keyboard is one of the main ways to communicate with a computer. There are many different types of keyboard, but most are very similar and allow you to accomplish the same basic tasks.

Mouse

The mouse is another important tool for communicating with computers. Commonly known as a pointing device, it lets you point to object on the screen, click on them, and move them.

There are two main mouse types: optical and mechanical.

i.                   Optical mouse: The optical mouse uses an electronic eye to detect movement and is easier to clean.

ii.                 Mechanical mouse: The mechanical mouse uses a rolling ball to detect movement and requires regular cleaning to work properly.

Mouse alternatives

There are other devices that can do the same things as a mouse. Many people find them easier to use, and they also requires less desk space than a traditional mouse. The most common mouse alternatives are below.

▶ Trackball: A trackball has a ball that can rotate freely. Instead of moving the device like a mouse, you can roll the ball with your thumb to move the pointer.

▶ Touchpad: A touchpad also called a trackpad is touch sensitive pad that lets you control the pointer by making a drawing motion with your finger. Touch pads are common on laptop computers.

Buttons and Parts on a Computer

Take a look at the front and back of your computer case and count the number of buttons, ports, and slots you see. Now look at your monitor and count any your find there. You probably counted at least 10, and may be a lot more.

Each computer is different, so the buttons, ports, and sockets will vary from computer to computer. However, there are certain ones you can expect to find on most desktop computers. 

Front of a computer case

Back of a computer case

The back of a computer case has the connection ports that are made to fit specific devices. The placement will vary from computer to computer, and many companies have their own special connectors for specific devices. Some of the parts may be color coded to help you determine which port is used with a particular device.

Peripherals you can use with your computer

The most basic computer setup usually includes the computer case, monitor, keyboard, and mouse, but you can plug many different types of devices into extra ports own your computer. These devices are called peripherals. Let’s take a look at some of the most common ones.

▶ Printers: A printer is used to print documents, photos, and anything else that appears on your screen. There are many types of printer, including inkjet, laser, and photo printers. There are even all-in-one printers, which can also scan and copy documents.

▶ Scanners: A scanner allows you to copy physical image or document and save it include as parts of an all-in-one printer, although you can also buy a separate flatbed or handheld scanner.

▶ Speakers/Headphones: Speakers and headphones are output devices, which means they send information from the computer to the user in this case, they allow you to hear sound and music. Depending on the model, they may connect to the audio port or the USB port. Some monitors also have built in speakers.

▶ Microphones: A microphones is a type of input device, or a device that receives information from a user. You can connect a microphone to record sound or talk with someone else over the internet. Many laptop computers come with built-in microphones.

▶ Web cameras: A we camera or webcam is a type of input device that can record videos and take pictures. It can also transmit video over the internet in real time, webcams also include a microphone for this reason.

▶ Game controller and joysticks: A game controller is used to control computer games. There are many other types of controller you can use, including joysticks, although you can also use your mouse and keyboard to control most games.

▶ Digital cameras: A digital camera lets you capture pictures and videos in a digital format. By connecting the camera to your computer’s USB port, you can transfer the images from the camera to the computer.

▶ Mobile phones, MP3 players, tablet computers, and other devices: Whenever you buy an electronic device, such as mobile phone or MP3 player, check to see if it comes with a USB cable. If does, this means you can most likely connect it ti your computer.

Inside a computer

Have you ever looked inside a computer case, or seen pictures of the inside of one? The small parts may look complicated, but the inside of a computer case isn’t really all that mysterious. This lesson help you master some of the basic terminology and understand a bit more about what goes on inside a computer.

Motherboard

The motherboard is the computer’s main circuit board. It’s a thin plate that holds the CPU, memory, connectors for the hard drive and optical drives, expansion cards to control the video and audio, and connections to your computer’s ports (such as USB ports). The motherboard connects directly or indirectly to every part of the computer.

CPU/processor

The central processing unit (CPU), also called a processor, is located inside the computer case on the motherboard. It is sometimes called the brain of the computer, and its job is to carry out commands. Whenever you press a key, click the mouse, or start an application, you’re sending instructions to the CPU.

The CPU is usually a two-inch ceramic square with a silicon chip located inside. The chip is inside usually about the size of a thumbnail. The CPU fits into the motherboard’s CPU socket, which is covered by the heat sink, an object that absorbs heat from the CPU.

A processor’s speed is measured in megahertz (MHz), or millions of instructions per second; and gigahertz (GHz), or billions of instructions per second. A faste4r processor can execute instructions more quickly. However, the actual speed of the computer depends on the speed of many different components-not just the processor.

RAM (Random Access Memory)

RAM is your system’s short-term memory. Whenever your computer performs calculations, it temporarily stores the data in the RAM until it is needed.

This short-term memory disappears when the computer is turned off. If you’re working on a document, spreadsheet, or other type of file, you’ll need to save it to avoid losing it. When you save a file, the data is written to the hard drive, which acts as long-term storage.

RAM is measured in megabytes (MB) or gigabytes (GB). The more RAM you have, the more things your computer can do at the same time. If you don’t have enough RAM, you may notice that your computer is sluggish when you have several programs open. Because of this, many people add extra RAM to their computer to improve performance.

Hard drive

The hard drive is where your software, document, and other files are stored. The hard drive is long-term storage, which means the data is still saved even if you turn the computer off or unplug it.

When you run a program or open a file, the computer copies some of the data from hard drive onto the RAM. When you save a file, the data is copied back to the hard drive. The faster the hard drive, the faster your computer can start up and load programs.

Power supply unit

The power supply unit in a computer converts the power from the wall outlet to the type of power needed by the computer. It sends power through cables to the motherboard and other components.

Expansion cards

Most computers have expansion slots on the motherboard that allow you to add various types of expansion cards. These are sometimes called PCI (peripheral component interconnect) cards. You may never need to add any PCI cards because most motherboards have built-in video, sound, network, and other capabilities.

Video card

The video card is responsible for what you see on the monitor. Most computer have a GPU (graphics processing unit) built into the motherboard instead of having a separate video card. If you like playing graphics-intensive games, you can add a faster video card to one of the expansion slots to get better performance.

Sound card

The sound card also called an audio card is responsible for what you hear in the speakers or headphones. Most motherboards have integrated sounds, but you can upgrade to a dedicated sound card for higher quality sound.

Network card

The network card allows your computer to communicate over a network and access the internet. It can either connect with an Ethernet cable or through a wireless connection (often called Wi-Fi). Many motherboards have built-in network connections, and a network card can also be added to an expansion cards.

Bluetooth card or adapter

Bluetooth is a technology for wireless communication over short distances. It’s often used in computers to communicate with wireless keyboards, mice, and printers. It’s commonly built into the motherboard or included in a wireless network card. For computer that don’t have Bluetooth, you can purchase a USB adapter, often called a dongle.

What is laptop computer?

A laptop computer is personal computer that can be easily moved and used in a variety of locations. Most laptops are designed to have all of the functionality of a desktop computer, which means they are generally run the same software and Open the same types of files.

However, laptops also tend to be more expensive than comparable desktop computers.

How is laptop different from a desktop?

Because laptops are designed for portability, they are some important difference between them and desktop computers. A laptop has an all-in-one design, with a built –in monitor, keyboard, touchpad (which replaces the mouse), and speakers. This means it is fully functional, even when no peripherals are connected. A laptop is also quicker to set up, and there are fewer cables to get in the way.

You’ll also have to the option to connect a regular mouse, larger monitor, and other peripherals. This basically turns your laptop into a desktop computer, with one main difference: You can easily disconnect the peripherals and take the laptop with you wherever you go.

Here are the main differences you can expect with a laptop.

▶ Touchpad: A touchpad also called a trackpad is touch sensitive pad that lets you control the pointer by making a drawing motion with your finger.

▶ Battery: Every laptop has a battery, which allows you to use the laptop when it’s not plugged in. Whenever you plug in the laptop, the battery recharge. Another benefit of having a battery is that it can provide backup power to the laptop if the power goes out.

▶ AC adapter: A laptop usually has a specialized power cable called an AC adapter, which is designed to be used with that specific type of laptop.

▶ Ports: Most laptops have the same types of ports found on desktop computer (such as USB), although they usually have fewer ports to save space. However, come ports may be different, and you may need an adapter in order to use them.

What is a mobile device?

A mobile device is a general term for any type of handheld computer. These devices are designed to be extremely portable, and they can often fit in your hand. Some mobile devices like tablets, e-readers, and smartphones-are powerful enough to do many of the same things you can do with a desktop or laptop computers.

Tablet computers

Tablet computers are designed to be portable. However, they provide a different computing experience. The most obvious difference is that tablet computers don’t have keyboards or touchpads. Instead, the entire screen is touch-sensitive, allowing you to type on a virtual keyboard and use your finger as a mouse pointer.

Tablet computer can’t necessarily do everything traditional computers can do. For many people, a traditional computer like a desktop or laptop is still needed in order to use some programs. However, the convenience of a tablet computer means it may be ideal as second computer.

E-readers

E-book readers also called e-readers are similar to tablet computers, except they are mainly designed for reading e-books (digital, downloadable books). Notable examples include the Amazon Kindle, Barnes and Noble Nook, and Kobo. Most e-readers uses an e-ink display, which is easier to read than a traditional computer display. You can even read in bright sunlight, just like if you were reading a regular book.

Smartphones

A smartphone is more powerful version of a traditional cell phones. In addition to the same basic features phones calls, voicemail, text messaging-smartphones can connect to the Internet over Wi-Fi or a cellular network (which requires purchasing a monthly data plan). This means you can use a smartphone for the same things you would normally do on a computer, such as checking your email, browsing the Web, or shopping online.

Most smartphones use a touch-sensitive screen, meaning there isn’t a physical keyboard on the device. Instead, you’ll type on a virtual keyboard and use your fingers to interact with the display. Other standard features include a high-quality digital camera and the ability to play digital music and video files. For many people, a smartphones can actually replace electronic like an old laptop, digital music player, and digital camera in the same device.