How do anti-virus applications protect systems?

Anti-virus applications protect systems by detecting, preventing, and removing malicious software like viruses, worms, and trojans.

Anti-virus applications are a critical component of any computer system's security infrastructure. They work by scanning files or directories for harmful software and use signature-based detection to identify threats. This involves comparing the contents of a computer's hard drive against a database of known malware signatures. These signatures are essentially the digital fingerprints of malware and are unique to each variant. When a match is found, the anti-virus software either deletes the malicious file or places it in a quarantine where it can't harm the system.

In addition to signature-based detection, many anti-virus applications also use heuristic analysis. This method involves analysing the behaviour of software to identify new or modified forms of malware that may not yet have a known signature. Heuristic analysis can be more effective at detecting zero-day threats, which are new types of malware that have not yet been identified and added to signature databases.

Another important function of anti-virus software is real-time protection or on-access scanning. This feature monitors the system continuously, checking files as they are opened or executed. If a threat is detected, the software takes immediate action to neutralise it. This provides a constant shield against malware, helping to prevent infection in the first place.

Anti-virus applications also often include additional tools to enhance system security. These may include email protection, which scans incoming and outgoing messages for threats; web protection, which blocks access to malicious websites; and firewall features, which monitor network traffic and block unauthorised access to the system.

In summary, anti-virus applications protect systems by using a combination of methods to detect and eliminate threats. These include signature-based detection, heuristic analysis, real-time protection, and additional security tools. By regularly updating their malware databases and algorithms, anti-virus applications can stay ahead of new threats and provide robust protection for computer systems.