A-Z Guide to Cyber Security

A lot of terms get thrown around when discussing cyber security - but this jargon doesn't mean a lot to your business. To help you cut through the clutter we have put together this A-Z glossary of common terms. If you see something particularly worrying, click the image on the right to take our 5-minute IT Security Self Assessment.

Remember - cyber criminals depend on businesses sticking their head in the sand. The best way to stay safe is to stay educated.



Software that prevents, detects and eliminates malicious programs on computing devices.


Software that detects and eliminates computer viruses.

Backdoor Trojan

A virus that enables remote control of an infected device, allowing virtually any command to be enacted by the attacker. Backdoor Trojans are often used to create botnets for criminal purposes.


A group of Internet-connected devices configured to forward transmissions (such as spam or viruses) to other devices, despite their owners being unaware of it.


Also known at computer crime or netcrime, cybercrime is loosely defined as any criminal activity that involves a computer and a network, whether in the commissioning of the crime or the target.


Distributed denial of service attack. An attempt to interrupt or suspend host services of an Internet-connected machine causing network resources, servers, or websites to be unavailable or unable to function.


An overarching term describing hostile and/or intrusive software including (but not limited to) viruses, worms, Trojans, ransomware, spyware, adware, scareware, and others, taking the form of executables, scripts, and active content.


An attempt to acquire sensitive information like usernames, passwords, and credit card details for malicious purposes by masquerading as a trustworthy entity in a digital environment.


Trojans that conceal objects or activities in a device’s system, primarily to prevent other malicious programs from being detected and removed.

Social Engineering

Non-technical malicious activity that exploits human interaction to subvert technical security policy, procedures, and programs, in order to gain access to secure devices and networks.


Malicious, non-replicating programs that hide on a device as benign files and perform unauthorised actions on a device, such as deleting, blocking, modifying, or copying data, hindering performance, and more.

Zero-Day Vulnerability

A security gap in software that is unknown to its creators, which is hurriedly exploited before the software creator or vendor patches it.