1.1-Types of computer
As you can see there's many different kinds of computers in your daily life. They appear to be in different forms, such as size, design, storage and many more. For the first type I would like to introduce to you the.....
UNIT 1.1.Desktop or Personal Computer (PC)
Desktops are widely used all over the world. You can see them in some places like the school, office etc. It's generally equipped with a Monitor
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| Monitor Drawn by me |
, keyboard,
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| Keyboard drawn by me |
mouse,
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| A mouse drawn by me |
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| System unit drawn by me |
Advantages:
- Its' processor is much faster than a laptops processor.
- Rarely has problems involving "Overheating" like laptops since its' size is much larger.
- Spare parts are usually cheap since they 're standardized.
Disadvantages:
- Lack of portability >> it's quite heavy and its' separate components are connect with wires.
- Files have to be copied and stored on a CD when you need to take them with you.>> If the files are large it would waste lots of time to complete downloading.
2.Laptop or Notebook
Laptops are similar to desktop computers only its' components are all together in it.This means that it's much easier to move from one work area to another. It's components are assemble together. The mouse has been removed, instead it is added with a pad (pointing device) which works like a mouse.
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| Laptop drawn by me |
- Portability
- Users are able to work anywhere, if their work requires Internet, they just simply access Wi-Fi.
- Since they are portable, loss and theft are key disadvantages.
- Battery life is limited.
- Keyboards and pointing device are not flexible.
- Laptops usually have problems with " Over-heating".
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| Netbook image from the internet |
Advantages:
- They are extremely portable, since they are much smaller than laptops.
- They are often very cheap , because less functions are equipped.
- Screens are smaller and less effective than normal laptops
- Small keyboards are difficult to use.
- Netbooks are not equipped with CD/ DVD drives, which might cause problems when you need it.
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| Mainframe computer image from the internet |
Advantages:
- These computers are capable of processing huge jobs, which involve using its large memory storage and fast processor speed.
- Able to solve complex problems.( These problems would take smaller computers longer to do.)
- Mainframes are so enormous that it could fill an entire room. They are not portable.
- Since mainframes are equipped with complex components it is difficult to setup.
- Requires specialist staff to operate.( Not anyone is able to use it )
- These components are really expensive.
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| PDA with a stylus drawn by me |
Advantages:
- Extremely portable => they are able to fit in pockets and small bags.
- Bigger screens than cell phones.
- Access to email and web.
- Often have qwerty keyboards.
- Designed for organizing information => diary, calendar, alarm clock, address book, etc.
- Difficult to use because of the tiny keyboard.
- Difficult to read long documents with small screen sizes.
- Version of software that have limited range of functions.(Difficult to complete task effectively.)
This is an advanced mobile phone that combines with the functions of a PDA, with these features:
-Web browser
-High-resolution touchscreen
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| Smartphone drew by me |
-Wifi access
Generally, most smartphones are equipped with a media player and camera.
Advantages:
- Online access to data.
- Better web browsing capability than normal cell phone.
- Able to accomplish many tasks at anywhere.
- One can integrate contacts' and phone numbers.
Disadvantages:
- Difficult to use since its' size is too small.
- Cost can be very high as most providers also want to use internet (which also costs a lot )
- When access to internet, web pages may not display or function entirely as the web pages expected.
7. Tablet
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| Tablet drew by me |
Advantages:
- Online access to data.
- Better web browsing capability than normal cell phone.
- Able to accomplish many tasks anywhere.
- High Definition (HD) screen.
- Easier to use since it's much bigger than a smart phone.
Disadvatages:
- Heavier than smartphones.
- Cost can be very high as most providers also want to use internet (which also cost a lot ).
- With its size, it's hard to keep in pockets.
Many types of computers are packed with their advantages and disadvantages. Still they're all special in many ways....
UNIT1.2- Hardware,software & Computer Components
Hardware- Physical parts of a computer
Software/Programes/ application
- Operating systems or System softwares it is where the application runs on. Without OS the computer will not work. For example: IOS, MAC, Window and linux.
- Applications or apps for short. It's that runs on operating system. For example: Microsoft Word, Google chrome and Photoshop.
Computer Component<- (Hardware)
- Everything inside the system unit are components. For example. Processor (Brain), Ports(the part where you can connect things like USB), Storage[Hard disk] {Drive}, RAM, ROM [Both are memory], Drives. The computer won’t work if it doesn’t have components.
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| http://my.opera.com/freeicons/blog/2009/09/29/pencil-sketch-style-computer-peripherals-free-clipart |
- Other hardware that isn’t in the system unit (things that are plug in the computer) are called External [Peri(f)pheral]. For example: keyboard, mouse etc.The computer will work if it doesn't have peripheral.
- Operating system is the program that make the computer and the extra programs inside the computer work. Therefore, operating system is themain program for every computers.
- Hardware is the physical parts of the computer.
- Application or short for apps are the extra programs to add into the operating system.
From this diagram it'll tell you that OS ( operating system) is the most important one among the others. OS can communicate with application and hardware. Though application and hardware cannot communicate with each others. Still the OS needs to run on hardware just like application needs to run on OS. Overall without the central communication, which is the operating system, others will not work.
UNIT 1.3 : The 4 main components of a computer system.
Lesson: 1 [6/9/13]
There're 4 main components(parts) of a computer system. That every computer has it ( including smartphone and tablet.) Each of them has its own important job.
- Processor- It's the most important one among the others. Without it the system will not work like a person without a brain. Every computer has it.
- CPU (Computer Processing Unit
2. Storage- It's where the computer keeps data.
- ROM
- RAM
- Hard disk(drive)
- SD card
- Thumbdrive
3. Input devices- Hardware used to put data in the computer.
- Keyboard ( Type in the information.)
- Mouse ( Put in information.)
- Touchscreen ( Put in information.)
- Scanner (Put in images)
- Monitor (Get images)
- Printer ( Get data )
- Speaker (Get sound )
- Projector (Get images)
- Earphone (Get sound )
- Headphone (Get sound )
This is how computer works.
Microprocessors
Microprocessors can be found in many devices not just only in the computers e.g. washing machine, a refrigerator etc. Microprocessor is a computer chip but did you know that there are 2 types of processor which are CPU and simple processor.
- CPU is in the computer because it is more powerful than the simple processor and it can do many different jobs e.g. opening up the programs.
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| Simple processor |
- Simple processors are mostly in the machines such as microwave because it can do just only 1 job or run a simple program e.g. the simple processor that is in the washing machine can only run a program to wash the clothes.
Main Memory
Main memory can also be called internal memory, central memory or primary memory. The main memory is a chip that is located very closely to the CPU and it is use for storing the data and instructions of a computer. Although, the main memory is not part of the CPU but it is directly connect with the CPU. There are 2 types of main memory which are:
- RAM (Random Access Memory) = RAM is a memory chip that is inside the system unit which is uses for storing data and running the programs while the computer is turning on. However, RAM can only temporary storing the data because if we turn off the computer, we'll lose the information that are store in the RAM [Volatile]. The advantage of RAM is making the computer run faster.
- ROM (Read Only Memory) = ROM is a memory chip that is inside the system unit. Another name for ROM is permanent memory because the data that are store inside the ROM is permanent which mean that although the computer is turn off but the information that is store inside the ROM won't be gone.
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| RAM |
| ROM |
| BIOS |
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| Portable hard disk |
Storage Devices
Other names for storage devices are backing/backup storage or store, secondary storage or external storage. Storage devices are used for storing all of the informantion when the computer is turning off but it is not the same as ROM because Rom is connected to the CPU but the storage devices are not. Storage devices can also be moved from one computer to another but ROM can't. Storage device is a peripheral . Portable hard discs and memory stick are examples of storage devices.
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| CD-ROMs |
* CD-ROMs and DVD-ROMs are not the same as ROM because ROM is a memory that is inside the computer but CD-ROMs and DVD-ROMs are storage devices that have large capacity or space that can store information. *
Unit 1.4 : Operating system
There are 2 types of O/S. Both types have the same functions but they are very different to use.
1. Graphical User Interface [GUI] : It is a system that uses pictures and icons to organize.
- Uses WIMP [ Windows, Icons, Menu, Pointing devices.]
- Example: Window 8, mac o/s, Andriod, IOS, etc.
Advantages: easy to customize, many programs can be run at the same time, it's easy to use [User-friendly] and it provides accessibility (people with disability will be able to use them e.g. blind people can use the speech regconition).
Disadvantages: Large storage (take up a lot of spaces) this is because lots of graphic like icons takes up spaces, need new hardware (powerful computer), unstable (crashes a lot).
2. Command Line Interface [ CLI ]
- Uses only text commands.
- Examples: Unix and MS-DOS.
The diffrent between CLIs and GUIs
GUIs are used by nearly everybody because it is easy to use. However, the users of the GUI can just only control the systems that the programs allow them but they won't be able to control all of the computer systems
CLIs are mostly used by the technicians and the specialists who need to go through all of the systems of the computer. If they know the commands of the CLIs it will make it eaiser for them to control and looking after the computer system.
Difference between hardware and Software
Computer hardware is any physical device used in or with your machine, whereas software is a collection of code installed onto your computer's hard drive; it is intangible. For example, the computer monitor you are using to read this text and the mouse you are using to navigate this web page is computer hardware. The Internet browser that allowed you to visit this page and the operating system that the browser is running on is considered software.Nearly all software utilizes hardware to operate properly. A video game, which is software, uses the computer processor (CPU), memory (RAM), and video card, all of which is hardware, to run. Word processing software uses the computer processor, memory, and hard drive to create and save documents.
In a computer, hardware is what makes a computer work. A CPU processes information and that information can be stored in RAM or on a hard drive. A sound card can provide sound to speakers and a video card can provide an image to a monitor. All of this is hardware.
On that same computer, software can be installed and allow a person to interact with the hardware. An operating system, like Windows or Mac OS, is software. It provides a graphical interface for people to use the computer and other software on the computer. A person can create documents and pictures using software.
