A file is a collection of related data given a unique name while a folder is named storage location on a storage media that contains related files

• The number of FDE cycles run per given time/second
• the frequency that the clock ‘ticks’
• 3.8 billion cycles/instructions per second

A PAN exist around a single person whereas a LAN covers a larger area

Direct Change-Over

• A date is chosen for the shutdown of the old system, then at that time, the old system
  is turned off and the new system is implemented

Phased

• Parts of the new system are implemented in stages or for a period of time, both the old and the new system are running together until all parts of the system are implemented.

• 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, ...)

• Unsigned integers store more positive values

 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

• Knowledge base – is the systems’ database of knowledge about a particular subject. It contains relevant facts, beliefs, assumptions and procedures for solving a particular problem
• Inference engine – this is the software that controls the search for knowledge in the knowledge base and produces conclusions. It takes the problem posed by the user and seeks to analyze it in order to arrive at a conclusion.
• User interface- this is the display screen that enables the user interact with the system.

• Extra bit on each data-byte that
•  Does not transmit data
• Makes the number of ones in a byte always even or always odd
• Error in the transmission of a bit will make the even/odd wrong
• The problem of two errors in one byte not being found
• Parity block

• A collection of related webpages under the same domain name

• Installing the latest versions of antivirus software
• Avoiding downloads from untrusted sites
• Scanning removable storage media for viruses before use
• Scanning attachments for viruses before opening or downloading

Memory management

• Manage the computer’s memory;
• It can control which parts of the memory are being used by which process

Processor management

• Manage the computer’s processor(s)CPU;
• Schedules of which processes are to be executed;

Input/output management

• Manages input/output devices;
• Interacts with/manages/handles the (automatic) installation of device drivers;
•  Handles peripheral device interrupts;
• the computer can communicate with the outside world;
• Control network communication;
• Allow devices to send and receive data;

Managing storage

• Manage secondary storage devices;
• Loading data and programs into the computer’s memory;
• Storage space management (disk quotas);
• To ensure that storage space is allocated fairly and efficiently to specific tasks\users;

Managing security

•  User authentication;
• To make sure that users must prove who they are to access the system;
• Protect against malware;
• Block access to specific vulnerable operations or system areas. For example, software can only be installed with admin access;

Managing applications

• Control access to applications;
• Prevent users or processes from using unauthorised programs // allow users or
• processes to use authorised programs;
• Control application access;
• Prevent/allow an application access to data (or devices);

 Control unit

Control Unit; Decodes instruction; Controls the fetching and writing of data;

Arithmetic Logic Unit/ ALU; Executes mathematical instructions;  Executes logical instructions; Compares values held in registers;

 Clock; Controls the number of instructions carried out each second;   allows the CPU to synchronize operations;

• more accurate/improved stock control/recording system/automatic
• reordering/automatic updating of stock file
• less staff/wages needed
• sales statistics now available
• faster throughput
• itemised receipt
• records every transaction
• records staff work rates
• less pilfering by staff/easier to identify pilfering
• less errors
• faster calculations
• links to EFTPOS

• Allows creation and management of user accounts
• Helps in troubleshooting of the network
• controls access to network resources
• Provides communication services
• configures network resources
•  

Is an arrangement of people, data, processes, communication and IT that interact to support problem solving

Components of an information system

• Hardware
• Software
• Data - information manipulated by software
• people- all people involved
• Processes - steps to accomplish a goal

• 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

• consists of values between 0–255 / 0–FFF
• values are separated by full stops/colons
• it is a unique address
• can be static or dynamic
• can be public or private
• can be IPv4 / have four groups of digits
• can be IPv6 / have eight groups of digits
• in IPv6 :: can replace groups of zeros.

a)  i)  Explain what is meant by the term volatile memory                                                            (1mark)

• Memory content is lost when the power is turned off

ii) What is normally stored in the non-volatile part of a computer’s main memory                       (1mark)

• The Computer’s BIOS

b) Explain why having cache memory can improve the performance of the CPU                         (2mks)

• Frequently used data/instructions are store in the cache; Meaning they don’t have to be fetched from the main memory;
• Data/instructions stored in the cache memory can be accessed faster (than data/instructions stored in the main memory) MAX 2