There are two types of Windows version.
1. Release verion
2. Build version
How to check the version
1. on Registry
HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion "CurrentMajorVersionNumber"==(REG_DWORD)0x0a "CurrentMinorVersionNumber"==(REG_DWORD)0x00 "CurrentBuildNumber"==(REG_SZ)17134 --- "CurrentBuild"==(REG_SZ)17134 "CurrentVersion"==(REG_SZ)6.3
2. by using command
C:> systeminfo