Antivirus – What is it and How Does it Work?
Antivirus is software that detects, prevents, and eradicates malware threats like computer viruses, worms, ransomware, Trojan horses, spyware, and other malicious programs. It monitors device activities and scans files, applications, network connections, and external devices to identify potential vulnerabilities hackers can exploit. It also alerts and allows users to scan individual devices on demand. It operates on individual computers, laptops, servers, and networks, and can include advanced features for large IT environments like centralized monitoring and firewall control.
It identifies and removes virus threats, including those that self-replicate or hide in cryptic code, from singular devices and entire IT systems. It typically analyzes websites, files, installed programs and apps, and day-to-day program behavior to flag suspicious patterns that might indicate malware infection or activity. It can also prevent data breaches and other cyberattacks by blocking unauthorized network access to devices, detecting malware that has already breached the perimeter, and removing it from a system.
Early antivirus programs used signature-based detection methods, comparing digital fingerprints of viruses against a database of known malware. But attackers quickly adapted by creating “oligomorphic” and more recently “metamorphic” viruses that encrypt or change their code to avoid matching the signatures of previously identified malware. These techniques require sophisticated, evolving detection methods.
Modern antivirus solutions use a combination of detection technologies, such as heuristic and machine learning, to analyze and isolate malicious behavior on a system or device. They often employ cloud-based technology to rapidly update malware definitions and detect new attacks as they emerge.