Yes on Windows 7 it only protects spyware, they made Microsoft Security Essentials previously for Windows XP, Vista and 7,
They used the Windows Defender name for Windows 8, 8.1 and 10, only different is it now provides full protection in 8, 8.1 and 10 with Defender for malware/viruses, ransomware, It's not the same as Windows 7 Version, scores good on Comparatives tests