Pass Check: GCSE Computer Science Challenge
Master GCSE Computer Science exam technique: binary and hexadecimal conversion, storage size calculations, command words, pseudocode conventions and trace tables.
Binary
A base-2 number system using only the digits 0 and 1, used internally by computers to represent all data and instructions.
Hexadecimal
A base-16 number system using digits 0 to 9 and letters A to F, used as a compact, human-readable shorthand for binary.
Bit
A single binary digit, either 0 or 1, and the smallest unit of data a computer can store.
Byte
A group of 8 bits, treated as a single unit and used as the standard base measurement of storage size.
Overflow error
An error that occurs when the result of a calculation needs more bits than the number of bits available to store it, causing data to be lost.
Bitmap image
An image stored as a grid of pixels, each holding colour data, whose file size depends on its resolution and colour depth.
Sample rate
The number of samples taken per second when converting an analogue sound wave into digital data, measured in Hertz (Hz).
Bit depth
The number of bits used to store each sound sample or each pixel's colour, which determines the precision and quality of the recording or image.
Pseudocode
A way of writing an algorithm using structured, code-like English and standard keywords, without following the exact syntax of a real programming language.
Trace table
A table used to record the value of every variable each time it changes as an algorithm runs, used to check the algorithm's logic or find errors.
Quick check
Mixed quiz
1. Which command word would ask you to point out the similarities and differences between a LAN and a WAN?
2. A scenario describes a school wanting to stop pupils accessing inappropriate websites on the school network. Which security or network measure would be most suitable?
3. A hospital needs to design a network that keeps patient data secure while allowing multiple departments to access shared records quickly. Which combination of measures is most appropriate?
4. During a timed exam, what should you do if you get stuck on a hard question worth few marks?
5. An exam question worth 9 marks asks you to discuss whether a company should move its data storage to the cloud. Which of these answer structures is most likely to gain high marks?
6. A company wants staff to access company files securely from home. Which technology is most commonly used to provide this secure remote access?
7. A company's server room requires 5 minutes to fully back up all its data every night, and this must happen without disrupting daytime staff. Evaluate the most sensible time to schedule this backup.
8. A network administrator notices unusually high outgoing traffic from a computer at night when no one is using it. Which security threat does this most likely suggest?