Essential Terms — C06

The Hamilton and Alexandra College · Year 12 · 2026

A glossary of every term you need to recognise and use correctly across C06. Click a term to expand its definition. The C06 pages — and the feedback graded against them — use these words, so learn them in the language the rubric uses.

flowchart TD
    R["C06 vocabulary<br/>66 terms"]
    R --> G0["Language and execution<br/>8 terms"]
    R --> G1["Operators<br/>3 terms"]
    R --> G2["Control structures<br/>11 terms"]
    R --> G3["Variables and constants<br/>5 terms"]
    R --> G4["Data types<br/>6 terms"]
    R --> G5["Data structures<br/>7 terms"]
    R --> G6["Data sources<br/>8 terms"]
    R --> G7["Functions and methods<br/>10 terms"]
    R --> G8["OOP features<br/>8 terms"]

Where the C06 vocabulary sits, and how much of it is in each group — the 9 sections below follow the same order. Revise the heavy groups first.

Language and execution

compiler

A program that turns source code into machine language that can be executed by a computer processor.

event

A special type of method that is called when an object's state changes.

flow of execution

The order in which instructions, conditions, and iterations are executed or evaluated.

graphical user interface (GUI)

A type of user interface that allows users to interact through visual elements such as windows, icons, and buttons.

hard-coding

To include fixed data in a program that cannot be changed during runtime and can only be changed by modifying the program source code.

instruction

A unit of code that can be executed by a compiler or interpreter.

interpreter

A computer program that directly executes source code without needing to have it compiled beforehand.

prolog

The information in an XML file that appears before the start of the document's contents, including information such as the XML version and character encoding that is being used.

Operators

arithmetic operator

A symbol in programming that performs basic mathematical operations such as addition, subtraction, multiplication, and division.

conditional operator

A symbol used to compare two values within a condition, such as equals (==), not equals (!=), greater than (>), less than (<), greater than or equal to (>=), or less than or equal to (<=). Used inside selection and iteration conditions to decide whether a branch runs or a loop continues. (Not to be confused with the ternary conditional expression, e.g. x if condition else y in Python — that's shorthand for an if/else selection, not a comparison.)

logical operator

A Boolean operator used to combine expressions, such as AND, OR.

Control structures

alternative execution

Code that is run if a condition is not met.

chained selection

A selection structure with more than one condition checked in sequence (e.g. if / elif / elif / else), where each branch can test a different condition. Execution stops at the first branch whose condition is true.

DO/WHILE

An iteration over a set of instructions, conditions, and/or iterations that is repeated for as long as a condition is met; it is always run at least once.

FOR

An iteration over a set of instructions that is repeated a predefined number of times.

infinite loop

An iteration that will never reach the condition upon which it can terminate.

nested selection

When a selection contains one or more additional conditions within its structure.

REPEAT/UNTIL

An iteration over a set of instructions that is repeated for as long as a condition is not met; it will always execute at least once.

selection statement

A control structure that allows a programmer to write lines of code that are only run when a particular requirement is met.

sequence

A set of instructions that executes line by line in the order that it is written.

switch/case

A selection structure that compares a single value or expression against a list of specific possible values (cases), running the matching branch's code (e.g. match/case in Python, switch/case in TypeScript). Unlike chained selection, every case tests the same expression for equality against a different value, rather than evaluating independent conditions per branch.

WHILE

An iteration over a set of instructions that is repeated for as long as a condition is met.

Variables and constants

casting

Converting a variable from one data type to another, such as converting a string to an integer.

constant

A fixed value that, once defined, cannot be altered during the execution of a program.

global variables

Variables that are defined outside any function and can be accessed by all functions throughout the source code.

local variables

Variables that are defined inside a function that can only be accessed by that function.

variable

A method of storing and labelling data to be referenced and manipulated in a computer program.

Data types

Boolean

A data type with one of two possible values, 0 and 1, usually referred to as False and True, respectively.

character

A data type representing any single meaningful unit, such as a letter, a number, a punctuation mark, a symbol or even a space.

data type

A method of classifying a variable to determine the data that variable can contain, as well as how that variable can be manipulated.

floating point

Computer representation of real numbers, with decimal places.

integer

A data type representing whole positive and negative numbers.

numeric

A data type consisting of whole numbers, referred to as integers, and decimal numbers, referred to as floating points.

Data structures

array

A list of elements indexed by position. In most programming languages, the first element has index zero.

data structure

A method of organising data to allow particular operations to be performed on it efficiently.

dimension

The direction or the level of organisation within a data structure, such as an array.

field

A single data item in a record (e.g. FamilyName).

record

A complete set of fields relating to an entity, such as a person.

tree

The structure of an XML file that contains a root element and all of its sub-elements.

two-dimensional array

A data structure that stores elements in a grid-like format, organised into rows and columns, allowing access using two indices.

Data sources

child element

Any sub-element of a parent element in an XML file.

CSV

A comma-separated value file, which is a delimited file separated by commas.

delimiter

The character used to separate data values in a delimited file.

parent element

Any element in an XML file that contains at least one sub-element.

plain text (TXT) file

A structured file that contains characters of readable data.

root element

A parent element to all other elements in an XML file.

text file

A structured file containing sequences of characters that are not encrypted, such as a plain text file or CSV file.

XML

Extensible Markup Language; a metalanguage that allows for user-defined tags and rules for encoding documents in a format that is readable by humans and machines.

Functions and methods

arguments

Specific inputs passed into a function that act as local, temporary variables.

function

A sequence of related code that has been given a name that can be called from other points in the source code.

function call

To execute the contents of a function.

function declaration

To name a function and its arguments.

function definition

To define (write) the contents of a function.

method

An action an object can carry out (e.g., window.refresh, golfClub.swing).

parameters

See arguments.

pass by reference

To pass data into a function as an argument so that it can be modified without needing to be returned.

pass by value

To pass data into a function as an argument so that it cannot be modified without needing to be returned.

return value

A value or set of values that is passed back to the origin of a calling function, often to be assigned to a variable, used in an equation, or tested within a conditional statement.

OOP features

abstraction

An object-oriented programming language principle that allows programmers to manage complexity by hiding implementation details and exposing only the essential features of an object.

class

A program code template for creating objects in object-oriented programming languages.

encapsulation

An object-oriented programming principle that involves bundling the data and methods that operate on the data into a single unit or class.

generalization

The process of defining a general class (superclass) that encapsulates common attributes and behaviors of more specific classes (subclasses).

inheritance

A method of basing an object or class on another object or class, taking on its attributes and methods and potentially extending upon them.

instantiation

In object-oriented programming, the process by which an object is created from a class.

object

Any instantiated class that a program can inspect and/or change, in terms of appearance, behavior, or data.

object-oriented programming (OOP)

A programming language based on the concept of objects that contain data in the form of fields or attributes and code in the form of methods.