Cambridge IGCSE Computer Science Vocabulary Review

A comprehensive set of vocabulary flashcards derived from the Chapter 7-10 revision notes, covering the Program Development Life Cycle, standard algorithms, pseudocode syntax, database management, and logic gates.

PDLC

The Program Development Life Cycle, which consists of the stages: analysis, design, coding, and testing.

Abstraction

A process during the analysis phase that keeps key elements required for a solution and discards unnecessary details.

Decomposition

The process of breaking down a complex problem into smaller, manageable parts.

Structure Charts

A hierarchical structure tool used in the design phase that shows the main system, subsystems, and the methods to reach them.

Totalling

The process of keeping a running total where values are added to a variable, often initialized to $0$.

Counting

Keeping track of the number of times a specific action is performed, such as incrementing a counter when a condition is met.

Linear Search

An algorithm that searches for a value in a list by checking every element one by one from the start until the item is found or the end is reached.

Bubble Sort

An algorithm that sorts an array by comparing adjacent elements and swapping them if they are in the incorrect order.

Validation

Automatic checks performed by a program to ensure that data entered is reasonable and acceptable.

Range Check

A validation check that ensures a value falls within a specified upper and lower limit, such as an age between $0$ and $120$.

Check Digit

A digit appended to a code, calculated from other digits, used to verify that the code was entered correctly.

Verification

The process of checking that data has been accurately entered or copied from one source to another, using methods like double entry or visual checks.

Normal Test Data

Data that the program should accept as valid to prove it processes correct inputs as expected.

Abnormal Test Data

Data that the program should reject, used to test if the software handles invalid inputs gracefully.

Extreme Test Data

Test values that sit at the very limits of the accepted range, such as the highest and lowest possible valid marks.

Boundary Test Data

Data used to check limits, consisting of extreme values and the values immediately outside the accepted range (which should be rejected).

Trace Tables

A technique used to simulate algorithm execution line by line to track variable values and record the output.

Syntax Error

An error in the program's code caused by using incorrect keywords or failing to follow the rules of the programming language.

Logic Error

An error in an algorithm that causes it to produce incorrect results even though it runs without crashing, often due to wrong operators like using $OR$ instead of $AND$.

Constants

Identifiers that represent values set at the start of a program that cannot be changed during execution.

INTEGER

A data type representing a whole number, such as $7$, $-9$, or $0$.

REAL

A data type representing a number that contains a fractional part or decimal point, such as $9.1$ or $0.0$.

BOOLEAN

A data type that can hold only one of two values: TRUE or FALSE.

Assignment Operator

The symbol $←$ used in pseudocode to assign a value to a variable or constant.

DIV

A library routine used to return the quotient after a division, omitting the remainder.

MOD

A library routine used to return only the remainder resulting from a division.

SUBSTRING

A string operation that extracts a specific number of characters from a string starting at a defined position.

CASE OF

A selection statement used to choose between several literal values, which is different from an IF statement that evaluates conditions.

REPEAT…UNTIL

A post-condition loop that executes at least once and continues until a specific condition becomes true.

WHILE…DO

A pre-condition loop that checks a condition before execution and may never run if the condition is false from the start.

Procedures

A block of code that performs a task but does not return a value, invoked using the CALL keyword.

Functions

A block of code that performs a task and returns a single value to the main program using the RETURN and RETURNS keywords.

Local Variables

Variables declared within a procedure or function that can only be accessed within that specific block of code.

Global Variables

Variables declared in the main program that can be accessed and modified from anywhere, including inside procedures and functions.

1D Array

A data structure that stores a collection of elements of the same data type under one name, accessed via a single index.

Primary Key

A field in a database table that uniquely identifies each record and cannot contain null values.

SQL SELECT

The SQL command used to fetch specified fields or columns from a database table.

NOT Gate

A logic gate that reverses the binary input value.

XOR Gate

A logic gate that returns TRUE if either input is TRUE, but not if both inputs are TRUE.

NAND Gate

A logic gate that returns TRUE if one or both inputs are FALSE.