Spybot Search & Destroy, commonly known as Spybot, is a free anti-malware and anti-spyware software for Windows. It is developed by Safer-Networking Ltd. and was first released in 2000. Spybot is designed to detect and remove various types of malware, spyware, adware, and other potentially unwanted software from a computer.

Spybot offers several features, including system scans, immunization (which helps prevent malware from infecting a computer in the first place), rootkit detection, and file shredding (which permanently deletes files from a computer). Spybot also includes a tool called TeaTimer, which monitors system changes and alerts the user if any changes are made by malware or potentially unwanted software.

In addition to its free version, Spybot offers a paid version called Spybot +AV, which includes antivirus protection in addition to its anti-malware and anti-spyware capabilities.

Overall, Spybot can be a useful tool for detecting and removing malware and other unwanted software from a Windows computer. However, it is important to note that no anti-malware software can offer 100% protection, and it is still important to practice safe browsing habits and keep software and operating systems up to date to minimize the risk of malware infections.