The Fetch – Execute cycle is a sequence of actions, performed by the processor as it fetches
a program instruction from its memory, determines what the instruction wants to do and
carries out those actions. The stages of the cycle are provided below.

• Fetch the instruction – the processor fetches the instruction from a memory address stored in a program counter and transfers the instruction, via a data bus, to an instruction register. At the end of the fetch operation, the counter points to the next instruction that will be read in the next cycle.
• Decode the instruction – the processor decodes the instruction stored in the instruction register, including getting any operands required to complete the instruction.
• Execute the instruction – the decoded instruction is executed.
• Store the result – the result generated by the execute phase is stored in the main memory, and/or sent to an output device. The program counter is updated with feedback from the arithmetic logic unit (ALU), to a different address from which the next instruction will be fetched.

• A compiler translates the whole program in one go whereas An interpreter translates each line of code (often an intermediate code) at run time
• A compiler produces an executable file that will run on the target hardware machine without the compiler being installed  A run time interpreter will be required at run time
• Compilers tend to be large complex programs Interpreters are smaller simpler programs
• Interpreted programs can be amended and run without translating whole program Compiled programs have to be re-compiled after a change
• Compilers compile programs that will usually only run on the target platform (hardware/operating system)  Interpreters will interpret same program (or intermediate code) on different (some virtual) platforms

• Simple technology is needed to develop both hardware and software.
• Digital devices are more reliable, small in size and use less power as compared to analog devices.
• Devices that read, process or output data in digital form are used in computers and other digital devices such as calculators.

• Realtime processing
• Batch processing
• Timesharing
• multiprogramming
• Online
• Batch
• Distributed

Explain the purpose of each of the following features of a spreadsheet chart (KCSE 2021, Q19 (a))

Legend

• Legends are a small visual representation of the chart's data series to understand each without confusion.

A data series

• is a row or column of numbers that are entered in a worksheet and plotted in your chart, such as a list of quarterly business profits
• A group of related data points or markers that are plotted in charts and graphs

Data Marker

• A symbol on the chart that represents a single value in the worksheet.
• A column, dot, pie slice, or another symbol in the chart representing a data value

https://www.lifewire.com/data-series-data-points-data-labels-3123411

• Sequential
• Random
• Serial
• Indexed-sequential

• Windows for example a word processing application and a spreadsheet

• Menus, for example, allow the user to perform operations or run applications such as right-click to create a new folder  

• Icons for example a picture of linked computers for networking

• Pointers(mouse or touchscreen)  for example to select items/trigger events  

• Shortcuts for example to frequently used applications for example having a shortcut to your mail client on your desktop

• File navigation for example when searching the hard disc for a file/folder using a browser

• copying / deleting / moving/sorting/naming/searching of files or folders for example copying of a file from the hard drive to a USB pen drive (File handling)

• Desktop customisation for example changing the colours and background image

• Copy and paste for example between applications e.g. copying a graph from a spreadsheet to a word processor

• Error messages for example provide users with error/warning/help messages for example ‘printer out of paper’ 

Hard disk drive

• to hold the operating system/communication and applications software/ISP software
• for storing files/information/cookies on backing store

RAM

• for data, computer programs and operating instructions which are moved into it/downloaded for data currently in use

DVD writer

• Films/videos/pictures/music/multimedia data downloaded/purchased

Modem

• link/dial up/establish communication with the Internet
• Convert digital signals to analogue/audio tones (and vice versa) Which can travel across the telephone system

• VM is used when RAM is full  i.e part of the secondary storage used as (temporary) RAM/VM
• Data from RAM is moved to the secondary storage/VM (to make space in RAM)
• RAM can then be filled with new data
• When data in VM is needed it is moved back to RAM

• They are small and fit in a small storage space
• They are portable hence can be carried when need to be used outside the office
• Low power consumption
• Have rechargeable batteries

Advantages

• no wires
• fast/high-speed wireless Internet access
• WLAN is faster than a modem or mobile
• WLAN for working at home one day a week/teleworkers
• see internet content away on the move
• create and send multimedia messages to mobiles or e-mail
• picture messaging - send photos/pictures text/sound/recorded
• greetings from mobiles to mobiles/PCs
• instant transmission - no busy signals/no searching for phone jacks
• download e-mail and file attachments on mobile
• watch live webcast on mobile/hotspot
• listen to streaming video on mobile/hotspot
• news/weather/sport/games while on the move
• access information from mobile anytime
• send/receive/delete e-mail while on the move
• wireless Inbox on mobile - to contacts and calendar
• view business appointments while out of the office on mobile
• send corporate e-mail while out of the office - even behind a firewall on mobile
• wireless internet connection from chat rooms for discussions with colleagues while on the move
• give visual demonstrations from mobile and colleagues watch back at the office

 disadvantages e.g.

• WLAN speeds are slower than Net access at work/narrow band width
• any one within the WLAN nodes range with an appropriate device can use your WLAN and broad band link
• any one who walks past your house or WLAN linked into a corporate system can access sensitive information or credit card details
• 3G phones not compatible with 2G phones
• Blue tooth - has limited range
• blocked signal/distorted signal/weak signal/lag
• health problems from microwaves

• Optical scanner is used read data by use a beam of light while a magnetic ink scanner is used to read data encoded/written using magnetic ink by magnetising the ink characters and translating them

• A software which can display a webpage on a user's computer screen

• Continual decrease in computer size
• Improved speed and power of processing
• Decrease in computer physical size and its related facilities cost

The booting process is the sequence of events that occur when a computer is turned on or restarted. It involves a series of steps that allow the computer's operating system to initialize and become functional. Here's a simplified explanation of what happens during the booting process:

1. Power-On Self-Test (POST): When the computer is powered on, the first thing it does is perform a Power-On Self-Test. During this step, the computer's hardware components, such as the CPU, memory, and storage devices, are checked for proper functioning. The POST verifies that all essential hardware components are present and operational.

2. Bootloader: Once the POST is completed, the computer looks for the bootloader. The bootloader is a small program stored in the computer's firmware or on the bootable device (such as the hard drive or a USB drive). It is responsible for loading the operating system.

3. Loading the Operating System: The bootloader locates the operating system's files and initiates the loading process. It may display a boot menu allowing the user to choose the operating system if multiple options are available. The selected operating system's core files are loaded into the computer's memory.

4. Kernel Initialization: The operating system's kernel, which is the central component responsible for managing system resources, is initialized. The kernel sets up essential components such as device drivers, memory management, and process management.

5. System Initialization: After the kernel is initialized, the operating system proceeds with system initialization. During this stage, various system services and processes are started, and hardware devices are initialized and configured. The operating system loads essential system files and prepares the environment for user interaction.

6. Login/Graphical Interface: Once the system initialization is complete, the user is presented with a login prompt or a graphical user interface (GUI). The user can then log in with their credentials or interact with the GUI to access the computer's functionalities.

• it generates and/or allocates an IP address

• file deletion
• file copying
• file renaming
• file retrieval
• file closing
• file reading

• Developing training materials
• Training computer users
• Conducting ICT examinations
• Managing the learning and examination process
• Developing guidelines for using the computer lab
• Planning the course content
•  

Phased:
Advantages:

• only a small part of the operation affected if new system fails
•  no need to pay for two sets of wages

Disadvantages:

•  time consuming (each part needs testing fully before expanding system)

Pilot:
Advantages:

• if new system fails, only that part will be affected
• possible to gradually train staff on pilot before whole system changes over

Disadvantages:

•  time consuming (waiting to see how pilot works before rolling out to rest of the organisation)

Direct:
Advantages:

•  less likely to malfunction since fully tested
• immediate benefits/less time wasted
•  reduced costs (only one system so no need to duplicate staff)

Disadvantages:

• disastrous if the new systems does fail

Parallel:
Advantages:

•  if new system goes down, there is a backup system in place
• possible to gradually train staff/staff have time to get used to the new system

• connecting wireless headphone to a phone
• Using a wireless mouse, keyboard etc
•