QCAA Digital Solutions key terms

A finite, ordered set of unambiguous steps that transforms inputs into a desired output, forming the logic behind any program before it is written in code.

A structured, language-neutral description of an algorithm using plain statements and indentation, letting designers show program logic without worrying about exact syntax of a real language.

A manual review technique where a programmer traces an algorithm or code by hand using sample inputs, recording variable values step by step to confirm the logic produces correct outputs.

A classification such as integer, real, string or Boolean that determines which values a variable may hold and which operations can legitimately be performed on those values.

The region of a program in which a declared identifier is recognised and usable; local scope limits a variable to one module, while global scope makes it visible throughout the program.

The mechanism by which data is supplied to a subprogram; by value sends a copy so the original is protected, while by reference gives direct access to the caller's variable.

The design practice of breaking a large program into smaller self-contained modules or subprograms, each performing one well-defined task, improving readability, testing and reuse.

A measure of how strongly one module depends on another. Loose coupling is desirable because modules can be changed or replaced independently with minimal effect on the rest of the system.

A measure of how closely the internal parts of a single module belong together. High cohesion means a module performs one focused task, making it easier to understand and maintain.

A data structure holding a fixed-size, ordered collection of elements of the same type, accessed by an index, allowing many related values to be processed efficiently with loops.

A searching algorithm that checks each element of a list in turn until the target is found or the list ends; simple to code but slow on large unordered data sets.

An efficient search that repeatedly halves a sorted list, comparing the target with the middle element, discarding the irrelevant half until the item is located or proven absent.

A procedure that arranges data into a defined order, such as ascending numeric or alphabetical, to speed searching and make reports readable; bubble, insertion and merge sorts are common examples.

Values selected to exercise a program, deliberately including normal, boundary and invalid cases so that correct behaviour and error handling can both be verified.

The systematic process of locating, diagnosing and correcting errors in a program, using techniques such as breakpoints, trace tables, print statements and systematic test runs.

A mistake that breaks the grammatical rules of a programming language, such as a missing bracket or misspelled keyword, which prevents the code from compiling or running at all.

A flaw in the reasoning of a program that lets it run without crashing but produce incorrect results, often caused by wrong operators, conditions or loop bounds.

An error that occurs only while the program is executing, such as division by zero or accessing a non-existent array element, often causing the program to halt unexpectedly.

A data storage model in which information is held in tables of rows and columns, with keys linking tables so that data is stored once and relationships are represented explicitly.

A field or combination of fields that uniquely identifies each record in a table; it cannot be duplicated or left empty, and it anchors relationships to other tables.

A field in one table that stores the primary key value of a record in another table, creating a link between the two tables and enforcing referential integrity.

A rule ensuring every foreign key value matches an existing primary key value, or is null, so that records cannot point to related records that do not exist.

The process of organising tables to reduce duplicated data and update anomalies, progressively removing repeating groups and partial dependencies to reach third normal form.

A modelling diagram showing entities as rectangles, their attributes, and the relationships between them with cardinality symbols indicating one-to-one, one-to-many or many-to-many associations.

A reference document describing each field in a database, including its name, data type, size, format, validation rules and description, supporting consistent design and maintenance.

Automated checking that data entered into a system is reasonable and within acceptable limits, using rules such as range, type, length and presence checks before the data is accepted.

Checking that data has been transferred or entered accurately, for example by double entry, parity checks or visual comparison against the source document, rather than checking that it is sensible.

A request for information from a database, expressed in a language such as SQL or through a graphical tool, selecting, filtering, sorting and joining records to answer a specific question.

A standard declarative language for creating and manipulating relational databases, with statements such as SELECT, INSERT, UPDATE, DELETE and JOIN for retrieving and changing stored data.

The process of analysing large data sets with statistical and pattern-finding techniques to discover previously unknown trends, correlations and associations that can inform decisions.

A central repository that consolidates data copied from multiple operational systems, cleaned and structured for analysis and reporting rather than day-to-day transaction processing.

The accuracy, consistency and reliability of stored data throughout its lifecycle, protected by constraints, validation, access controls, backups and audit trails.

The transformation of readable data into an unreadable cipher form using a key, so that intercepted information cannot be understood without the corresponding decryption key.

The process of verifying that a user or system is who they claim to be, commonly through passwords, tokens or biometrics, before access to protected resources is granted.

The extent to which a software solution can be used by its intended audience to achieve goals effectively, efficiently and with satisfaction, covering learnability, consistency and accessibility.

The overall quality of a person's interaction with a system, including emotions, perceptions and ease of completing tasks, shaped by interface design, feedback and responsiveness.

Designing solutions so people with disabilities or varied abilities can use them, through features such as keyboard navigation, alternative text, sufficient contrast and resizable text.

A development approach that builds a solution through repeated cycles of planning, prototyping, testing and refining, allowing requirements and feedback to shape each successive version.

A preliminary working model of a solution, ranging from a paper sketch to an interactive mock-up, used to clarify requirements and gather user feedback before full development.

A project approach using short iterations, cross-functional teams and continuous stakeholder feedback to deliver working increments of software, adapting readily to changing requirements.

Legally protected creations of the mind, such as software code, designs and written content, covered by copyright, patents, trademarks and trade secrets.

Automatic legal protection giving the creator of an original work, including source code, exclusive rights to copy, adapt and distribute it for a defined period.

The legal terms under which software may be used, modified and shared, ranging from proprietary end-user agreements to open-source licences that grant specific freedoms and obligations.

The trail of data a person leaves online through posts, searches, purchases and metadata, which can be collected and may affect reputation or privacy long afterwards.

A person's right to control how their personal information is collected, stored, used and shared, protected in Australia by legislation such as the Privacy Act.