1. Introduction to computer fundamentals - guide
Aaron atuhe
@uncle_eliot
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2. Information Communication Technology (ICT)
ICT means the scientific means of sending and receiving information using scientific means (computers, networks, internet e.g.) which requires sending understanding and receiving feedbacks.
ICT tools - Radios, Tvs ,Computers, Phones, Masts, Satellite , e.t.c
Benefits/advantages
New Communication Methods
New Industries
Globalization
Cost effectiveness
Creation of new jobs
Greater Availability
Bridging the cultural gap
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3. Definition of Computer
A computer is a multipurpose electronic machine which operates under the control of instructions stored in its own memory that is capable of accepting data, processing the data, storing it, and finally outputting the processed data (information) through its output devices in a form that is usable by human being
Data:
This is the basic facts of any event in the life such as names, cost, prices, date, time etc
(Unorganized facts) e.g. lists of students in the school irrespective of their classes, sex or age.
Information:
This is data that has been turned into a more meaningful form that would make immediate sense to any user. I.e. processed data (organized facts) example of processed data include: printed documents, headed tables e.t.c
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4. Information processing cycle
Describe the information processing cycle. (Is the process where data is transformed into information)
The first three operations (input, process, and output) are performed to convert data into information, while the fourth operation (storage) refers to a computer’s electronic reservoir capability. To reinforce the information processing cycle, consider how each phase is performed in the “human computer” (i.e., the human brain) while completing a common task, such as learning a telephone number
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5. ADVANTAGE S OF COMPUTERS
Speed: Computers work at very high speed and are much faster than humans. A second is very large time period time for computer. A computer can perform billions of calculations in a second. The time used by a computer to perform an operation is called the processing speed. Computer speed is measured in Mega Hertz (MHz).
Storage: A computer can store a large amount of data permanently. User can use this data at any time. We can store any type of data in a computer. Text, graphic, pictures, audio and video files can be stored easily. The storage capacity of the computer is increasing rapidly.
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6. Accuracy: Accuracy means to provide results without any error
Accuracy: Accuracy means to provide results without any error. Computers can process large amount of data and generate error-free results. A modern computer performs millions of operations in one second without any error. Communication: Most computers today have the capability of communicating with other computers. We can connect two or more computers by a communication device such as modem. These computers can share data, instructions, and information. The connected computer are called network. 
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7. Disadvantage of using Computers
Unemployment where a job that could be done by 100 people is now being done by one person using the computer and within a short time.
Cost i.e. the initial cost, cost of training and cost of maintenance
Delicate i.e. you must handle it with a lot of care
Viruses, it’s a program which is designed to disorganize the proper functioning of the computer system, it can be spread easily using the internet or networked computers
Pornography more especially computers on internet which can even show sexual acts
Crackers: is a person who access information illegally on the network and he goes on to carry out malicious actions on it.
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8. COMPUTERS USAGE IN OUR SOCIETY
Research how computers are being used in our society in the following areas
Education
Health
Banks
Research
Communication
Defense
Recreation areas
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9. Characteristics of Computers
speed,
reliability,
Storage
Efficiency.
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10. How a computer works
Data is entered into the computer through the input devices like keyboard then its received by
the main memory (RAM) which stores it temporary as it waits to be processed,
its then sent to the CPU for processing and finally
its outputted through the out put devices like the monitor.
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11. A COMPUTER SYSTEM
A System: is a set of interrelated elements working together in an integrated way to achieve a set of objectives.
The components of a computer system include
Hardware
Software
Data
User
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12. Components for Hardware They are four in number Input devices
Computer Hard ware Hardware is the tangible computer equipment such as a CPU, keyboard, mouse, monitor, etc.
Components for Hardware 
They are four in number
Input devices
Processing devices
Storage devices
Output devices
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13. These are components that process data into information. E.g CPU
Input devices:  
input data and instructions in computers for example Keyboard, Mouse, Scanner for graphics, and Joystick for playing games and modem plus others.
Processing Devices
These are components that process data into information. E.g CPU
Central processing unit (CPU): The heart of the computer, this is the component that actually executes instructions. The CPU comprise of three major components
Control Unit
ALU(arithmetic Logic Unit)
Registers
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14. Functions of control unit
It interprets instructions stored in the main memory (RAM) and gives instructions to the relevant parts of the computer system like
out put devices to Monitor
Storage devices to floppy, Hard disk, flash
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15. 2.Arithmetic Logic Unit (ALU)
It’s for calculations, its function is to handle all the arithmetic and logic operations of the computer system for example additions, subtraction e.t.c
3: Registers.
This is a component which stores instructions temporarily in the CPU while waiting to be handled by ALU.
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16. Output device:
These are devices that let you see/display what the computer has accomplished processing for example Monitor, Printer Speakers etc.
Storage devices
These are devices that store data &information. They are divided into primary storage & secondary storage devices
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17. COMPUTER SOFTWARE
Computer software: refers to programs which enable computer hardware to function/operate effectively, i.e , a software that instructs the hardware on what to do and how to do it.
Examples include, MS word, MS excel, Windows, MS DOS, UNIX, Linux
Types of software:
Software is basically divided into two types:
System software
Application software
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18. System software:
These are programs which control and support all other computer programs and the hardware i.e, they manage the computer resources and ensure efficient running of the computer system.
System software is divided into
Operating system software &
System utilities 
Operating system:
These are the programs that manage the computer hardware resources and ensure efficient working of the computer. E.g DOS, MS windows, Linux, UNIX
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19. Functions of operating systems:
Memory allocation and loading of programs, before processing commences, operating system load the program to be used in RAM from the hard disk.
File management: the OS controls and manages the use and access of files on connected computers (network)
The OS starts and shut down the computer
Errors reporting, during the program execution, if there occurs errors of any sort , the operating system furnishes a message to the user e.g, saving on the floppy disk which is not there , the errors comes as “floppy disk not in the drive”.
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20. The OS provides an interface between the user and the computer hardware,
Memory management , the OS manages the use of memory (RAM) by allocating it for use and de allocating after at shut down
System security , the OS is responsible for the system security by making sure that only the authorized users are allowed to assess the files
Process management, The OS manages the functioning of the processor and all the processing job or activities
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21. Utility programs
These are system programs that are designed to help analyze, configure, optimize, configure, maintain or manage a computer. E.g DirectX, Microsoft Magnifier , System File Checker , Drive Converter e.t.c
These utility programs perform the following tasks,
Leaking of programs together to form a ready executable program
Copying of files
Deleting of files
Maintaining and repairing of file, computer Hardware etc
Loading programs in memory with the help of operating system
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22. Application software
These are programs that are designed to help the user achieve a specific task/ goal. E.g
Ms Access
Ms Word
Ms PowerPoint
Ms Page maker
Ms Publisher
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23. Specialized application packages
These are generally categorized into two main types, Specialized application packages (in house/custom programs) and General application packages
Specialized application packages
Include payroll, grading system used in school, registration system e.t.c, they are generally used to perform a single minded task . 
They meet special needs for an organization or company therefore they are dependable i.e make life easy for the users
These packages are expensive interms of paying the programmer to design a program
They are not flexible since they were designed for special tasks
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24. General application packages
These are programs which are used to perform general tasks in an organization such as Ms access, ms excel, Ms word
General purpose packages are cheap, They are flexible since they were designed for many tasks
The only shortcoming is :
They don’t help you achieve a specific goal broadly
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25. Memory
Memory is the internal storage areas in the computer. The term identifies data storage that comes in the form of chips, and the word storage is used for the memory that exists on tapes or disks. Moreover, the term memory is usually used as shorthand for physical memory, which refers to the actual chips capable of holding data. Therefore, memory is both hardware and software. Memory is devided into primary and secondary memories.
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26. Primary memories
Primary memory is storage where your computer stores instructions and information about programs it is currently running. E.g RAM, ROM, Cache.
Random Access Memory (RAM) is used by the computer as a temporary storage area for the processing activity. Any data that you are using or inputting is temporarily stored in the RAM, where it can be manipulated and used by the computer
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27. ROM (read-only memory) It is where your computer stores instructions that it uses when it boots (starts) up. ROM is non-volatile memory. That is to say, any information stored in ROM remains intact even when the computer is powered off.
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28. Secondary memories
This is memory outside the main body of the computer where we store programs and data for future use.
Secondary   storage  media   are non volatile  memories. This means  the  information  is not lost when power goes off. E.g hard disk, flash disks, floopy cds e.t.c
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