• Distributed data processing is where computers located in physically separate location transmit data after processing to a server computer that updates the master file. Time-sharing on the other hand is where various terminals transmit data to be processed by a central computer's CPU. Each terminal's tasks are allocated a time slice of the CPU

• A physical file contains the original data whereas a logical file does not contain any data
• A physical file contains one record format while a logical file can contain up to 32 record formats
• A physical file can exist without a logical file while a logical file cannot exist without a physical file

• less errors on input
• requires less storage space
• validation
• quicker to input
• quicker to find

• Real-time OS reads information from input devices and must respond within a short duration of time to ensure correct performance
• Distributed OS distributes computation among several physical processors which do not share memory or clock

• she had actually described verification
• data could be incorrect, therefore same incorrect data typed in twice
• accept description of validation process e.g. range check

Transcription Errors: Transcription errors involve the incorrect entry of data due to mistakes made during the copying or typing process. These errors can occur when transferring information from one source to another.

• Real-time processing is where data is processed as it is received and the output is made available immediately to influence the ongoing activity
• Interactive processing is computer processing in which the user can modify the operations appropriately while observing results at critical steps

• Sequential processing occurs in the order that the tasks are received while distributed processing where more than one computer or CPU is used to run specific programs.

        Misreading error

• Sequential
• Random
• Serial
• Indexed-sequential

• 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

State four threats that compromise data integrity

(i) Jobs collected together for processing at a later time
(ii) Output produced quickly enough to affect the next input
(iii) User has direct contact with the processor
(iv) User cannot communicate directly with the processor

• hexadecimal is easier (for humans) to read (than binary);
• numbers are displayed in a more compact way (in hexadecimal than in binary);
• it is quicker to type in (hexadecimal numbers than binary numbers);
• it reduces the risk of typing errors (in hexadecimal numbers than binary numbers);

• Binary can represent two states because computer circuits use transistors, which can either be on or off

• Unsigned integers store more positive values

• Computer systems use binary/ones and zeros/voltage on or off;
• Sound is analogue/continuous;
• Computers use digital data/discrete values

Taking a four-digit 0  binary number i.e (0000)2

• two's complement has only one value for zero

(a)Explain why programmers prefer to represent instruction in hexadecimal rather than in binary