designing software

32-bit computer system

a computer system with 32 bits of memory addresses

64-bit computer system

a computer system with 64 bits of memory addresses

application

software used to perform work or complete larger tasks; examples of popular applications include Microsoft Word and Excel, Adobe Photoshop and Mozilla Firefox browser

array

an indexed set of related elements; all elements within an array have a numeric index and are of the same data type

associative array

a collection of (key, value) pairs where each key is unique in the collection

Boolean

a logical data type; can hold on of only two possible values, true or false

camel case

a naming convention used in programming whereby each word or abbreviation in a phrase after the first word begins with a capital letter; there are no spaces or punctuation using camel case

central processing unit (CPU)

the 'brain' of a digital system; the handler of most of a system's data manipulation

character

a data type representing a single letter, number, symbol, punctuation

character encoding

code that allows a computer program to interpret binary digits (0s and 1s) into meaningful units representing characters and numbers. ASCII, UTF and Unicode are types of character encoding

class

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

collision

when two different input values to a hashing function output the same hash value

communication hardware

hardware that transmits data between computers and networked devices

complier

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

complex instruction set computing (CSIC)

a type of microprocessor design that contains large sets of computer instructions; intended to compute complex instructions in an efficient way

constants

fixed (unchanging) values during a program's execution; e.g. pi or the number of Australian states and territories

constraint

a restriction on what can and cannot occur in the creation of a software solution external to the solution itself

data structure

a method of organizing data to allow particular operations to be performed on them efficiently

data type

different forms that variables and data may take, which determine the data that a variable may contain, and how the data or variable may be manipulated

debugger

a tool used to identify errors in computer software

dependent task

a task that requires one or more other tasks to have been completed in order to begin

dequeue

to remove and return a value from the start of a queue

dictionary

an associative array, also referred to as a map or symbol table

digital systems

a elements such as hardware and software that, when connected, form a network

driver

a computer program that controls a particular device that is attached to, or part of, a computer

economic constraint

a constraint on the creation of a software solution that relates either to time or budget, or to both

editor

specialized application software for creating human-readable programming instructions

enqueue

to insert a value at the end of a queue

field

a single data item in a record

first in first out (FIFO)

a type of access to queued data, whereby the first element in a queue is the first element out of the queue

fit for purpose

well suited for a role or purpose

floating point number

computer representation of real numbers, with decimal places

functional requirements

requirements of a digital solution that are directly related to what the solution will do

Gantt chart

a project management tool for displaying project schedule information

graphical user interface (GUI)

a form of user interface that allows users to interact with an application or piece of software

graphics processor unit (GPU) a very fast and expensive processor specifically designed for high-speed image processing in graphics cards

hash function

a function that takes a key value and returns another, related, value that is normally smaller than the original value

hash table

a data structure that uses a hash function to map keys to values by computing an index that is related to, but smaller than, the initial key

high-level programming language

a programming language that is more or less computer-independent, typically using natural language elements

Hungarian notation

a naming convention used in computer programming, in which the name of the variable or function determines its purpose and its data type or structure

imperfect hash

a hash function where two or more keys can be computed to have the same hash index

index

position within an ordered list, such as an array

input devices

instruments and peripherals, such as keyboards, that allow users to give data and commands to software and the operating system

integer

a data type representing whole positive and negative numbers; a number without a fractional or decimal component

integer overflow

a condition occurring as a result of a mathematical operation where the output exceeds the maximum or minimum integer value that can be stored on that computer system

Integrated Development Environment (IDE)

software that provides tools to programmers to aid in programming, such as source code editing, syntax highlighting, code completion, debugging aids, or tools to help construct a user interface

interface

within software, the place where people control the program, enter data and receive output

interpreter

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

last in first out (LIFO)

a type of access to stacked data, whereby the last element in a stack is the first element out of the stack

linked list

a data structure containing an ordered set of elements where each element is connected to the next element in the list

low-level programming language

a programming language that is heavily relied on the architecture of a particular computer, with commands closely linked to processor instructions

maintainability

the extent to which a solution is easy to look after once it has been put in place

milestone

the achievement of a significant stage in a project; has zero time duration

mock-up

a sketch showing how a screen or printout will look, which is used to aid in the design of an interface

naming convention

an agreed set of rules by which to name files, folders and source code elements such as variables, functions, classes, methods and objects

NAND RAM

a type of non-volatile storage technology that does not require any power to store data

network-attached storage (NAS)

dedicated file storage that allows multiple users and clients to access data on a centralized disk

node

an element in a linked list; contains a data element and a pointer to the next node in the list

non-functional requirements

characteristics that the user or client would like the solution to have; often tied to solution constraints

non-technical constraints

factors that may limit or restrict solution development, specifically related to legal, social, usability or economic factors

numeric

a data type consisting of whole numbers, referred to as integers, and decimal numbers, referred to as floating point numbers

object

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

operation system (OS)

the software program that manages a computer's hardware and runs programs

output devices

instruments and peripherals that display information from a computer in human-readable form

perfect hash

a hash function where no two keys can be computed to have the same hash index

platform

a combination of operating system (OS) and central processing unit (CPU)

pointer

a variable that stores the memory position of another variable's value

pop

to remove an element of data from the top of a stack, moving all stack elements left over up on one place

portability

the extent to which a solution can easily be used in different operating environments

ports

physical connectors (sockets) for cables

primary storage

random-access memory (RAM), which provides storage for data, information and soft ware during program execution

processing hardware (CPU, GPU)

hardware that runs the operating system, utilities and applications

project plan

a formal document that is used to guide a project's timeline, allowing for the coordination and monitoring of tasks, including their sequencing and the amount of time required to complete each task

properties

characteristics; e.g. width, color, visibility

pseudocode

code that designs algorithms in a clear, human-readable, language-independent format

push

an element of data inserted at the top of a stack, moving all current stack elements down one place

queue

a 'First In First Out' data structure, storing elements to be processed in order

random-access memory (RAM)

a type of computer memory that can be accessed randomly; it is most often volatile memory that is lost if power is removed

record

an indexed set of related elements; all elements within a record have a field index and may be of different data types

reduced instruction set computing (RISC)

a central processing unit (such as ARM) that has smaller instruction sets than complex instruction set computing (CISU) CPUs

reliability

how much a solution can be depended on to function as designed, and for how long

robustness

how well a software solution responds to errors that occur when the software is being used

scope

boundaries or parameters of the solution; what it will it not do

scope creep

when a client changes the scope of a project (by increasing it) during the life cycle of the project

secondary storage

(HDD, SSD) permanent storage

slack time

the length of time that a task can run over time before it affects other tasks

snake case

a naming convention used in programming in which each word or abbreviation in the middle of a phrase is joined to one before it using an underscore

source code

the human-written and human-readable version of a program

stack

a 'Last In First Out' data structure

storage structure

places in memory holding data that is being used by a program; includes variables, arrays, dictionaries and objects such as GUI objects

string

a data type representing a set or sequence (collection) of characters

syntax

the structure of statements in a programming language

system software tools

software tools used by a computer to manage hardware and run the user's programs; for example, the operating system (OS), device drives and communication protocols

task

any activity within a project timeline that needs to be completed within a defined period of time

technical constraints

constraints related to the hardware and software available for a project

thin client

a lightweight computer that has been optimized to work with a server-based computing environment; the server does the majority of the processing and computing

uptime

time during which a machine, solution or application is operational

usability

the extent to which a system is easy to learn and use

utilities

usually small, single-purpose software tools that do a specific job or add functionality to an operating system

variable

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