Data Types and One-Dimensional Arrays
Select and implement characters, strings, integers, real numbers, Booleans and one-dimensional arrays.
How to study National 5 Computing Science
Move from functional requirements to designs and implementation, trace data and code carefully, and support testing and evaluation with evidence.
Core concepts
Concept 1
A character holds one symbol, a string holds a sequence, and numeric values use integer or real types.
Exam cue: Choose a type from the values and operations required, not from how the value happens to look.
Concept 2
A Boolean represents true or false conditions.
Exam cue: When tracing an array, record both its index range and the value at each position.
Concept 3
A one-dimensional array stores multiple values of the same type under one name and indexed positions.
Risk pitfalls and guardrails
Storing a count as a real number without need.
Guardrail: Check option route, data type, valid boundary, loop condition, array index, identifier and expected output before committing to the response.
Treating a one-dimensional array as a single scalar value.
Guardrail: Check option route, data type, valid boundary, loop condition, array index, identifier and expected output before committing to the response.
Memory anchors
Character
One letter, digit or symbol stored as a single character value.
String
A sequence of characters treated as text.
Integer
A whole-number value suitable for counts and discrete quantities.
Real
A numeric value that can include a fractional part.
Boolean
A value with two logical states, true or false.
One-dimensional array
An indexed collection of values of the same data type.
Checkpoint rule
Do the check-up only after you can summarize each concept in one sentence and identify one dangerous pitfall from memory.
Knowledge Check (after reading)
Short check-up to confirm understanding of this module.
Check-up Questions
A Boolean expression tests age >= 12 AND age <= 17. Which age passes?
Which condition accepts a code equal to 'A' or 'B'?
Answer all questions to submit.
Next step personalized recommendations
Continue learning
Move forward only after this module is stable.
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