IGCSE Computer Science Paper 2 Definitions Worksheet: 8.1a Data Types and Variables and 8.1b Sequence, Selection and Iteration (Modules 347–357)
Name:
Date:
Class:
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Key terms
Write what each term means, in your own words.
1
LCASE(Text)
2
UCASE(SUBSTRING(Name, 1, 1))
3
meaningful identifier
4
PascalCase
5
//
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// explain purpose
7
DECLARE TotalScore : INTEGER
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DECLARE INPUT OUTPUT
9
DECLARE Count : INTEGER
10
Count <- 0
Answer Key
IGCSE Computer Science Paper 2 · Modules 347–357 · Student wording will vary for definitions
1LCASE(Text) — Returns the text with every character in lower case, e.g. LCASE("Hi") gives "hi". The original variable is unchanged unless you assign the result to it.
2UCASE(SUBSTRING(Name, 1, 1)) — Nesting string functions: the inner SUBSTRING runs first, then UCASE changes its result. This gives the first letter of Name in capitals, such as an initial.
3meaningful identifier — A name that describes what a variable or constant holds, such as TotalToPay instead of T, so the program is easy to read and maintain.
4PascalCase — Each word starts with a capital. Name arrays with nouns (StudentNames); name functions and procedures with verbs (CalculateTotal, DisplayMenu) to show what they store or do.
5// — Starts a comment. Everything after // on that line explains the code to people and is ignored when the program runs, so it never changes what the program does.
6// explain purpose — A good comment explains why a section of code exists or a tricky step, without repeating the code word for word. Put it at the same indentation as the code it describes.
7DECLARE TotalScore : INTEGER — Pseudocode layout convention: keywords in UPPER CASE, identifiers in PascalCase, and lines inside a statement indented four spaces. Meta-variables use angled brackets, like <identifier>.
8DECLARE INPUT OUTPUT — A complete program declares variables and a CONSTANT, reads values with INPUT, processes them with assignments, then shows results with OUTPUT, using meaningful names and // comments.
9DECLARE Count : INTEGER — Names a variable (Count) and gives its data type (INTEGER) before use. Other types: REAL, STRING, BOOLEAN. Identifiers are capitalised with no spaces.
10Count <- 0 — The <- operator stores the value on its right in the variable on its left. Count <- 0 puts 0 into Count. It is assignment, not a test for equality.