I.T definitions IEB

1 NF

A table with a primary key, no repeating groups and no data redundancy.

2 NF

A table in 1NF and partial dependencies were removed.

3 NF

A table in 2NF with no transitive dependencies.

Acceptable User Policy (AUP)

A set of rules drawn up by the company management to protect the company, its network, resources, devices and data from misuse.

Accessor method

A method that returns the value of an object's private field.

Accuracy

The degree to which the stored value measures against the actual value. For example, the number of decimal places for numeric data.

Address Bus

Transfers the address of instructions and data between RAM and the CPU

Address Resolution Protocol (ARP)

A protocol that links the device's MAC address (frame) to its IP address (packet).

ADSL

An old telephone communication technology that transmits data along copper cables from the nearest telephone exchange to a location.

Adware

Unwanted content that automatically displays or downloads when browsing the Internet.

Anti-Malware

Software necessary to safeguard a computer against malicious threats.

Anti-Virus

Software that detects malicious software then deletes or quarantines it based on the program's behaviour (signature).

Append

To add data to the end of an existing file.

Application Software (App)

Software that carries out specific tasks for the user. All application software requires an operating system.

Archive

Removing files and storing them in a separate compressed location for space saving and later use.

Argument / Actual Parameter

A value or variable in a call statement sent to a method header.

Arithmetic Logic Unit (ALU)

A part of the CPU that performs arithmetic and logical calculations.

Artificial intelligence (AI)

The simulation of human intelligence in computers designed to think and act like humans.

Assembler

Translates assembly into machine code. Each instruction directly corresponds to a machine language instruction.

Assign

A variable is given a value, such as x = 3.

Asymmetric Encryption

Two non-identical keys used to encrypt and decrypt a message called the public and private keys.

Atomic Data

A single value within a field

Attenuation

The loss of signal strength over a distance.

Attribute

The same as a field or property.

Audit Trails

When database data is changed, the audit trail records the timestamp, username, accessed fields, and the modified data values.

Augmented Reality

A technology that places interactive digital content over real scenes.

Backup

Copying of files or folders in case of data loss - usually to a separate location.

Bandwidth

The maximum amount of data that can be transferred at one time. Measured in bits per second (bps).

Bandwidth Theft

Unauthorised accessing wireless bandwidth.

Barcode

A simple pattern of thin and thick lines that are decoded by the scanner to represent data.

Basic Input Output System (BIOS)

Non-volatile software stored in ROM to initialise the computer.

Big Data

A massive volume of structured and unstructured data that is difficult to process using traditional database and software techniques.

Biometric Device

A device to input and analyse human physical data such as fingerprints, voiceprints and retinal/iris scans to uniquely identify an individual.

BitTorrent

A peer-to-peer protocol in which multiple peers can transfer data between each other. Files are split into smaller parts to increase upload and download speeds. Once a peer has the complete file, it becomes a seed that other peers can use.

Black Hat Hackers / Crackers

Malicious hackers (crackers) who illegally access computer systems and networks for personal gain.

Blockchain

A decentralised, distributed, and public digital ledger to create trust. Blockchains act as a shared database, distributed across large peer-to-peer networks with no single point of failure.

Bluetooth

A wireless technology standard for sending data over short distances, using short-wavelength radio transmissions

Botnet / Zombie Army

A vast number of Internet-connected devices that send transmissions (including spam or viruses) to other Internet devices without the owner's knowledge. Often used in a DDOS.

Bounded Media

Communication channels, consisting of physical cabling, commonly used for wired LANs.

Bridge

A device that connects network segments, forwarding data packets to the next network segment if the MAC address is not in the current segment, reducing network traffic.

Broadcast

A communication sent to multiple nodes in the network. The communication is not secure.

Browser Cache

Previously accessed websites are stored on your local computer. If the website is accessed again, it will be loaded from the local computer instead from a remote website.

Browser extension

A small software module that provides customisation for a web browser.

Bytecode

The compiled version of the source code. E.g. code.class.

Candidate Key

A minimal super key

Check Digit

An extra digit, produced by an algorithm, to validate the existing digits in a number.

Check Sum

A test to verify data transfer by performing a calculation (such as a sum) on the bits transferred.

Class

A template to instantiate objects combining fields and methods into a single unit.

Client-Server

A single dedicated networked computer that provides services (file storage, email, printing) to other nodes/devices on the network.

Client-Side Scripting

Scripts that are executed by the client's browser.

Clock Multiplication

Sets the ratio of internal CPU clock rate to that of an external clock

Cloud Computing

On-demand remote computer services providing by Internet-connected servers, such as file storage, databases, applications, and processing power.

Cloud Storage

Storing data on remote servers, accessible from any Internet-connected device.

Co-Processor

An additional parallel processor to the CPU that performs specific tasks, e.g., GPU and FPU (Maths co-processor).

Code Window

The window where you, as a programmer, type in the source code, such as a Java program.

Command Line Interface (CLI))

A text-based interface, with commands entered and executed at the command prompt.

Compiler (One Stage)

Converts source code to object code if there are no syntax errors. The object code (.exe file) is executed. E.g. Delphi

Compiler (Two Stage)

Converts source code to bytecode if there are no syntax errors. The bytecode is interpreted and executed. E.g. Java

Complementary Metal-Oxide-Semiconductor (CMOS)

Battery-backed, volatile memory that stores hardware settings and user settings. It is accessed by BIOS during the POST.

Completeness

All the required fields in a database have values.

Component

A circuit chip placed directly on the motherboard

Composite Key

A combination of fields to form a primary key.

Composition

There is a has-a relationship between two objects. One object is a field of another object.

Compression

The process of reducing file size takes up less storage space and quicker Internet transfer.

Constructor

A method to assign values to the fields of an object.

Control Bus

Transfers signal between RAM and the CPU such as Read From Memory (RFM) and Write To Memory (WTM)

Control Unit (CU)

A part of the CPU that coordinates the processing of instructions.

Cookies

A small text file stored in a user's browser to record their history and preferences.

Correctness

Data that conforms to an approved or conventional standard or agrees with fact, logic, or known truth.

CPU / Processor

A motherboard component that processes instructions.

Creative Commons License

A licence where the author retains copyright of their work but allows people to copy and distribute the work (documents, source code) on condition the author is acknowledged.

Crosstalk

Signals in adjacent wires interfere with each other.

Currency

Data is up-to-date or not outdated.

Cyberbullying

The sending, posting, or sharing of negative, harmful, false, or mean content about a person using digital devices.

Dark Web

Non-indexed web pages hidden from standard search engines accessible using an anonymising web browser.

Data

Raw unprocessed information

Data Bus

Transfers instructions and data between RAM and the CPU

Data Mining

A set of techniques for discovering hidden, valid and potentially useful patterns or trends in a data set.

Data Redundancy

Unnecessary repetition of data produced by removing repeating groups as a result of first normal form.

Data Warehouse

The storage of an organisation's large volume of data (usually big data) produced from various sources.

Database Management System (DBMS)

Software that manages and controls a database. This includes permissions, backup, referential integrity and access control.

Declare

A variable is assigned a type. E.g. int x; or Gogga bug.;

Deep Web

Non-indexed web pages that cannot be accessed by a search engine, such as web pages behind a paywall, requiring sign-in credentials.

Deletion Anomaly

The unnecessary loss of data as a result of a deletion of a record.

Delimiter

Separates tokens in the Scanner class.

Denial of Service (DOS)

An attempt to make a server or network resource unavailable to its users.

Dependencies

One field is related to another field in a database.

Derived Data

One field is calculated from another field,

Digital Certificate

An organisation's Certificate Authority (CA) data file proving the organisation's identity. It cryptographically binds an entity's public key to specific attributes relating to its identity.

Digital Heritage

Texts, databases, images, videos, audio, emails, software, and web pages that should be protected and preserved for current and future generations.

Digital Signature

A user can "sign" a document by encrypting data with their private key. If the document can be decrypted with the matching public key, then the document can be proved to be sent by the user.

Disk Cache

A hardware mechanism for improving the time it takes to read from or write to a hard disk

Disk Defragmenter

Rearranges fragmented data on a mechanical hard disk so the data can be loaded and saved more efficiently. It reduces the latency of the hard disk drive.

Distributed Denial of Service (DDOS)

A DOS attack originating from multiple coordinated Internet devices (bots) to render a service useless.

Domain Name Servers (DNS)

A protocol that associates domain names to IP addresses.

Download

The process of receiving data from a remote server to a local computer

Driver

System software that communicates with a device by converting data into a format understandable by the device. Each device must have a driver.

Dumpster Diving

Obtaining discarded data such as invoices, phone records, organisational information, sensitive data printouts and discarded hardware to manipulate people.

Duplicate Data

When two fields have the same value. This is NOT data redundancy and must not be removed through normalisation. For example, two people have the same colour car.

Dynamic Binding

Using the object's appropriate overridden method in an inheritance hierarchy at run-time.