• Application software refers to software that is designed to help the computer user to accomplish specific tasks
• Examples of application software include; Internet browsers, word processors, spreadsheets, databases etc
• System software is software that performs tasks needed to operate the hardware and provide services to other software
• Examples Operating Systems, Networking software, utility programs(encryption, backup, disk defragmentation software, ...)

• It is an address to a resource on the internet

MAR( memory address register)

• Stores the address/location where data will be read/written/accessed/fetched
• stores address/location of data/instruction being processed
• stores address/location of data/instruction next to be processed

MDR or  memory data register

• Stores the data/instruction that is fetched/read from memory
• stores the data that is to be written to memory
• stores the data/instruction from the address in the MAR
• stores data/instruction next to be processed

 Program counter

• Stores the address/location of the next instruction to be run
• stores the address/location of the current instruction being run

Accumulator

• Stores the result of manipulation/process/calculation

a)Spreadsheets                                                                                                                               (2mks)

• Microsoft Excel
• Lotus 1-2-3
• Google Sheets
• OpenOffice Calc

                                           Any 2 @ 1mk

b) Word processors                                                                                                                          (2mks)

• Microsoft Word
• Wordpad
• Corel WordPerfect
• Lotus Word Pro

                                         Any 2 @ 1mk

1. Virus scanning / Anti-virus. Used to locate and delete viruses / scans and compares files with databases of known viruses.
2. Firewall: checks data packets / examines source address / filters out unexpected packets.
3. Back up. Copies data onto a separate storage device for use if the original data is lost or corrupted.

Any two from:

• Registers
• Clock
• CU
• ALU

• All the characters and symbols that can be represented by a computer system.
• Each character and symbol is assigned a unique value.

(b) One disadvantage of using the Unicode character set, instead of the ASCII character set, is

that the text stored takes up more storage space

• Each character is encoded using more bits

 A single executable file is produced 

The executable program is portable between machines

The program source code is not available

Code can be optimised/made more efficient 

Entire source code file is converted at once

No special environment is needed to execute the code 

It creates object/machine code

Error report is provided at the end of the compilation

• Encrypt network traffic
• Use of Firewall(s)
•  Anti-virus software
• Password protect the database

• Protection against Password-related Vulnerabilities: Traditional password-based authentication methods are vulnerable to various risks, such as weak passwords, password sharing, or password theft.
• Stronger Access Control: Biometric readers add an additional layer of access control to laptops. Even if someone gains physical possession of the laptop, they would still need the authorized user's biometric data to unlock it and access the data. This helps prevent unauthorized individuals from accessing sensitive information stored on the laptop,
• Audit Trail and Accountability: Biometric authentication systems often come with built-in logging and auditing capabilities. This means that each time someone accesses the laptop using their biometric data, it can be recorded and associated with a specific user. This creates an audit trail, allowing organizations to track and monitor access to laptops and establish accountability in case of any security incidents or breaches.

DVD - optical media which use one spiral track; red lasers are used to read and write data on the media surface; makes use of dual-layering technology to increase the storage capacity

ROM - non-volatile memory chip; contents of the chip cannot be altered; it is often used to store the start-up routines in a computer (e.g. the BIOS)

SSD/ Solid State Drive/memory (SSD)

non-volatile memory device that uses NAND flash memories (which consist of millions of transistors wired in series on single circuit boards)

Blue Ray -  optical media that uses blue laser technology to read and write data on the media surface; it uses a single 1.1 mm polycarbonate disc

20. a) The figure shows a network design. Use it to answer the questions that follow.

NB/ The diagram dor 20 (a)  is at the bottom

b. Explain the function of each of the following in the network

I     Router                                                                                                             [2]

- connects school LAN to the Internet/identifies the best route for data transmission/forwards data packets between a computer network and the Internet

II   Firewall                                                                                                                                  [2]

Hardware/software that filters unauthorized access to or from the school’s LAN

III  File Server                                                                                                                                [2]

Provides location for shared files/disk access/resources

c. State two categories of software that must be installed in a computer so that users can use it to access the Internet.                                                                                                                                  [2]

• Network operating system
• Browser e.g. I.E, Mozila, Google (accept examples)
• System drivers
• Protocol

d) State four ways in which computers may be used to manage data in a research environment.         [4]

The guiding principle is the candidate must mention the use and the technology to score

e.g.

1. Use of databases in data manipulation (Technology is database and the use is data manipulation)

2. Use of scanner to aid in data capturing

3. Use of Internet to communicate researched work

4. Use of printers to generate reports

5. Use of databases r hard disk to store data

etc etc

e) Some computer companies have opted to use the Internet to provide shared processing resources and online application services to users. State three advantages that this approach will have on their customers.                                                                                                                                 [3]

- The guiding principle is benefit/enhancement to the customer

• Customer will not be required to have powerful processing devices
• Customers can access services from anywhere
• There will be cost reduction for the customer
• Customers can collaborate with remote users
• Customers can access services at any time of the day
• Customers can upload/backup work in the cloud/Internet

It has a header

• that contains the destination address
• that contains the packet number
• that contains the originator’s address

It has a payload

It has a trailer.

Multi-tasking - It is a data processing modes where a single CPU processing more than one task or program apparently at the same time

Time-sharing - a processing mode where a single CPU processes tasks from more than one user apparently at the same time

Time-sharing - this is a processing mode in which the CPU serves two or more users with different processing requirements ( tasks)

On-line processing - is a mode of processing where the result of data processing transaction is available immediately

Real-time processing - is a mode of data processing in which the time interval required to process and respond to inputs is so small that the response itself is useful for controlling the physical activity of a process

• once instructions are given, the processing runs automatically hence requiring little supervision
• tasks are processed as a group hence reducing the cost
• It is faster since the since runs automatically
• there is increased output since the processor works without any interruption

Word wrap - Is a word processing feature in which a word that does not fit in the current line is automatically moved at the start of the next line

Justification - refers to aligning text on both left and right margins

Drop cap - Make the first character of a paragraph occupy more than one line below it

• the pain felt in muscles, nerves and tendons caused by repetitive movement and overuse.
• Injury as a result of repetitive use of parts of the body while performing work
• Strains and injuries due to prolonged typing and use of the mouse

• Sequential
• Random
• Serial
• Indexed-sequential

• This approach causes minimum disruption