1. Computers in Perspective.pdf

COMPUTER COMPETENCY Computers in Perspective Presenter – Jennifer Gachukia ([email protected])  Computer  A device that is a combination of electronic and electro- mechanical components.  Used for analysis, calculation, and computation of data, storage, editing and produc...

COMPUTER COMPETENCY Computers in Perspective Presenter – Jennifer Gachukia ([email protected])  Computer  A device that is a combination of electronic and electro- mechanical components.  Used for analysis, calculation, and computation of data, storage, editing and production of information in the form of graphics, text and/ or sound.  It is made up of hardware and software.  Software are the programs that translate instructions that a user gives to the computer into a language the computer understands and enables the computer to convey the output.  Advantages of a Computer  It is efficient  It is fast thus time saving  Saves on space  It is accurate  Environmental friendly  Holds research materials  Flexibility between programs  Disadvantages of a Computer  Cost  Training  Resistance to change  Require human skills (no common sense)  Unemployment  Health problems  Virus attacks  Reduced human interaction  Overreliance  Access to power  Elements that make up a computer system  Hardware – Electro-mechanical part of a computer or equipment used in a computer room  Software - Sets of instructions that tell the computer what to do, when and how to do it  Data – Raw unevaluated facts and/or figures to be processed  Information – Refined, summarized, categorized, and manipulated data into a form used for decision making. It is the product of data processing.  People – It is argued that a computer exhibits/ possesses almost all the characteristics of a human being but only lacks the intelligence of its own to perform a task so it depends on the intelligence of a human being  Connectivity – Manner by which various individual components and devices are interconnected together  Classification of Computers  Computers are classified on the basis of their functionality and size.  According to functionality, computers are classified as: 1. Analog computers – Process continuous data and present variables by physical quantities e.g. flow, temperature, pressure, voltage, time. All the analog computers are special purpose computers. 2. Digital computers – Represent physical quantities with the help of digits and numbers (0s & 1s). These numbers are used to perform arithmetic calculations and also make logical decision to reach a conclusion, depending on, the data they receive from the user. 3. Hybrid computers – Combine both analog and digital characteristics. The hybrid system provides the good precision that can be attained with analog computers and the greater control that is possible with digital computers, plus the ability to accept the input data in either form.  Analog Digital It functions on discrete numbers system. Its functions on physical analog system. The calculations in this system are primarily converted to equations and later converted into electrical The calculations in this system are converted into binary numbers (i.e., 1s and 0s). signals. To function, it requires discrete numbers. To function, it requires physical analog. It gives output in the form of discrete values. It gives output in the form of ‘graph’. Accuracy comparatively is less. Accuracy is very high. Performs at a low speed. It performs at a very high speed. Difficult to make changes, as it is less flexible. It is highly flexible. It has memory of low capacity. It has memory of high capacity. Its application is limited to certain applications. Its application is applicable to a number of applications. It is hardly applicable for the business applications. It is very much suitable for the business applications. It cannot process alpha-numeric data. It can process alpha-numeric data. It requires RF technology. It requires IP networking. Static channel assignment. Automatic channels exist as required.  Classification of Computers  According to size, computers are classified as: 1. Microcomputers (Personal Computers - PCs)  Cheap to purchase  Have small memory hence work slowly  Accessed by one person at a time 2. Mini-computers  More expensive than microcomputers  Have a bigger memory than microcomputers  Are bigger in size than microcomputers  Can be accessed by several persons using several monitors at the same time.  Classification of Computers 3. MainframeComputers  Serve hundreds of users simultaneously  Larger than the first two  Very expensive  Have a bigger memory than the two  Used in banks, airlines, insurance companies etc 4. Super Computers  Most expensive  Work fastest as they have the biggest memory  Can be used by thousands of users simultaneously  Uses of Computers 1. Education 2. Health/ Medicine 3. Science 4. Business 5. Entertainment 6. Government bodies 7. Recording information 8. Analyzing movements  Safety & Preventive Maintenance  Preventive maintenance – Performing proactive maintenance in order to prevent system problems.  Reasons for preventive maintenance include: i) Saves money – Avoiding problems will save money in the long run compared with laying out for components/ repair jobs ii) Saves time – The procedures are quite simple compared to troubleshooting/ repair procedures iii) Improves performance – Some parts of the system will degrade in performance over time and preventive maintenance helps to improve the speed of your system in this respect iv) Safeguard data – Data is secure once the system is running effectively  Diagnostic/ Corrective maintenance – Performed to correct an already existing problem.