Anti-virus programs protect computers from threats by detecting, preventing, and removing malicious software, commonly known as malware, including viruses, worms, and spyware. They operate by scanning files and applications for known malware signatures and suspicious patterns, alerting users to potential threats. Real-time protection features monitor system activity continuously, blocking threats before they can infiltrate the system. Additionally, these programs often include regular updates to adapt to new and emerging threats. By providing layers of defense, anti-virus software plays a crucial role in maintaining system integrity and safeguarding user data.