Microsoft Corporation - (Free)
Windows Defender is a software developed by Microsoft that defends the computer against pop-ups, slow performance, security threats caused by spyware and other unwanted software.
Although it requires a genuine Windows, Windows Defender is a powerful tool that detects spyware and unsolicited programs. It integrates with Windows to protect the computer by identifying and eradicating spyware on the system: pop-ups, slow performance, security threats caused by spyware and other unwanted software.
For optimum efficiency the software works in the background to protect your computer in real time . The software also takes advantage of the SpyNet network , not enabled by default , which allows them to connect users to better fight against spyware when a system is infected , up the information.
Windows Defender features Real-Time Protection, a monitoring system that recommends actions against spyware when it's detected, minimizes interruptions, and helps you stay productive. This antivirus is the equivalent of Microsoft Essentials and it is automatically installed on Windows 8.