(i) Crop - used when handling a graphic and there is a need to remove some of the portions in the graphic

(ii)Transparency - used when there is a need to make background of a graphic visible

• A non-volatile store of data

• (Cache) Stores regularly accessed instructions/data
• Reduces the need to access instructions/data from the main memory
•  Makes up for the difference in speed of the CPU and main memory

(i) Incorrect use of language, e.g. PLINT instead of PRINT
(ii) A mistake in the structure of the solution, e.g. a jump goes to the wrong line
(iii) Inappropriate arithmetic is used, e.g. division by 0 is attempted

• Standards specify a set of rules for hardware and/or software used in network communications. Because all manufacturers must adhere to the standards when manufacturing network hardware or software, it means that all devices should be able to communicate, regardless of manufacturer.

• Access Controls: Authentication of users in order to access files
• Performing regular patches of updates
• creating secure accounts with required privileges
• scrutinizes all incoming and outgoing packets of data through a firewall
• encryption of data, during transmission
• Log files to detect any breach

• Registers are small amounts of memory available that hold data fetched from memory or data waiting to be stored in memory. A temporary holding place for the instruction that has been fetched.
• The system clock purpose is to determine the pace of the cycle, each tick of the clock a part of the fetch-execute cycle occurs. Regulates the timing and speed of a computers systems functions.

Without a primary key, a table in a database may have duplicate rows, making data not uniquely identifiable. This can lead to issues with data integrity and challenges in maintaining relationships between tables. Retrieving and updating specific records becomes problematic, and setting referential integrity constraints is impossible, potentially leading to loss of data.

IMAP

• Retrieves/accesses/downloads (a copy of an) e-mail
• Allows synchronisation/management of account

SMTP:

• Sends/forwards/transmits e-mai

Benefits

• The user is not restricted to the predetermined options//the GUI uses icons and set menus
• The user has more control over the computer settings//in GUI computer settings are protected from the user
• Uses less memory than GUI
• Requires less processing power for the interface
• More processing power is made available for the task

Drawbacks

• The commands used have to be learnt
• The commands used have to be remembered
• The commands used have to be typed in/entered exactly
• Have to remember the exact path/correct name of application
• More prone to errors on data entry Commands have to be typed in//in a GUI can use touchscreens/mice
• Tends to be used by specialist people//GUI is more user-friendly and can be used by non-experts

• Firmware is a software program permanently etched into a hardware device such as a keyboards, hard drive, BIOS, or video cards.
• Device drivers are operating system-specific and hardware-dependent. A device driver acts as a translator between the hardware device and the programs or operating systems that use it. 
• Firmware is a software that controls a system, and firmware's functionality ranges from performing basic tasks like minimal I/O controls to full-fledged software system running with simple or no OS, with scheduler, memory management, etc. 
• A driver, on the other hand, is usually part of the operating system that performs the specific task of controlling a hardware component like a display or USB controller, etc., and gives an interface to use the hardware by Operating system and applications.

• Users need to ensure that their software is licensed

• 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’ 

• online storage
• incremental backup
• full backup
• RAID (level 0, 1, 10)
• uninterruptible power supply (UPS)

State the characteristics of each of the following network topologies (KCSE COMPUTER STUDIES 2021 )

i) Mesh Topology  (2mks)

• a host/node is connected to one or multiple hosts
• a   host/node in point to point connection with every other host or a few hosts
• hosts/nodes in mesh topology also work as relays for other hosts which do not have point-to-point links

(ii) Ring Topology (2mks)

• each host/node connects exactly to two other hosts
• data travels around the ring in one direction through all intermediate hosts
• failure of any host results in the failure of the whole ring

• data must be up to date
•  data can only be read/used for the purpose for which it was collected
• data must be adequate, relevant and not excessive
• data must be accurate
• data must be destroyed when no longer needed/don’t keep longer than necessary
• data user must register what data stored
• data must be used/collected fairly and lawfully
• data must be held securely
• data must be protected from accidental damage
• only authorised personnel can have access to the data
• fines are imposed for data mis-use
• data should not be passed on to a third party without permission
• a person can view data and have it changed/removed if incorrect

• understand the current system
• produce data flow diagrams/system flowchart
• identify user/client requirements/objectives
• interpret user/client requirements/objectives
• agree requirements/objectives with the user/client
• collect data from the current system
• fact finding (e.g. questionnaires, interviewing, etc.)
• problem identification

• By use of an ergonomic keyboard
• She should take regular breaks from her computer and stretch her joints
• She should use standard furniture with an upright backrest to reduce strain on the back

 Control unit

The organisation of files is in a hierarchy/tree structure
A node is either a folder/directory/sub-folder/sub-directory or the file itself
The top node/folder/directory/drive is the root