How does Windows Defender detect viruses, malware, and spyware?

Windows Defender is a built-in security tool in the Windows operating system. It helps protect users from viruses, malware, and other malicious software. Windows Defender has a number of features designed to detect and remove malware in real time, as well as provide periodic scans and scans on demand.

Windows Defender uses a combination of methods to detect malicious software. First, it uses behavior-based detection, which involves analyzing programs and processes that are running on the computer in order to determine if they exhibit suspicious behavior or if they are similar to known malware. It also uses signature-based detection, which looks at files and compares them to known signatures of known malware.

In addition, Windows Defender uses heuristics and cloud-based protection to detect and prevent the spread of new and unknown malware. Heuristics is a form of artificial intelligence that uses a set of rules to evaluate a program’s behavior and make a decision about whether it is malicious or not. Cloud-based protection leverages data from Microsoft Security Intelligence Center (MSSIC) which contains information from millions of computers around the world, and helps Windows Defender to identify and block malicious software faster.

Windows Defender also monitors for suspicious changes made to the registry and system files, and alerts users if any malicious activity is detected. It also checks programs that are downloaded from the internet, and prevents the user from running a program if it is deemed dangerous.

Moreover, Windows Defender uses real-time protection technology that continuously monitors activity on the computer to detect malicious behavior, and can alert the user if something suspicious is happening. It can also block malicious websites, downloads, emails, and other files that could contain malicious software.

Windows Defender also provides periodic scans and scans on demand. A periodic scan will scan the computer on a regular basis, while a scan on demand will scan only when requested by the user. This allows users to check for infections that may have gone undetected, as well as provide a way of verifying that their computer is clean.

Overall, Windows Defender is an effective tool for detecting and removing viruses, malware, and spyware. It utilizes a variety of methods to detect malicious software, and provides real-time protection, heuristics, cloud-based protection, periodic scans, and scans on demand.