keylogging: the act of capturing and recording a computer user’s keystrokes in a covert manner. Keylogging software is sometimes included as part of a computer virus and can be used to steal account passwords and financial information. 

botnet: a group of computers which have been breached and controlled by a third party and coordinated to collectively perform the same task, such as sending out spam emails or executing a denial-of-service attack.

phishing: the attempt to acquire sensitive information such as passwords and credit card details by posing as a trustworthy entity, such as a bank or service provider, in electronic communication. 

spyware: software which collects information about users without their knowledge. Most spyware is used to track an internet user’s activities for the purposes of advertising. Malicious spyware, such as keyloggers, may be used to steal important information. 

ransomware: a type of computer virus which restricts a user’s access to their own files, demanding that a ransom is paid to remove the restriction. Paying the ransom is never recommended, as it may lead to additional demands or compromise the user’s information.

trojan: a computer virus which infects users by disguising itself as a safe, standard file, including email attachments or useful software. The term is derived from the Ancient Greek story of troops hiding inside of a wooden horse to infiltrate the city of Troy.

DDoS attack: A distributed denial-of-service (DDoS) attack is an attempt to render a website or service unavailable by overwhelming it with large amounts of web traffic. A DDoS attack utilizes numerous computers to provide a large volume of superfluous traffic, either slowing down or forcing the target offline. 

worm: a worm is a computer virus designed to automatically spread itself to other computers through existing network connections, email, instant messages, etc. 

To see an expanded selection of malware terminology, check out Lavasoft’s malware cartoons on Pinterest.