If you are using Windows XP, the voice of Microsoft Sam (US male) has been installed by default. Beginning with Windows Vista and Windows 7, Microsoft Anna (US female) is the default and only English voice. On Windows 8/8.1, there are three voices available: Microsoft David (US male), Zira (US female), and Hazel (UK female). On Windows 10, there are two US English accent voices: Microsoft Zira (female) and David (male).
For those who are using Windows 8/8.1/10 computers, you will get Microsoft speech synthesis voices in English US, English UK, English India, German, French, Italian, Spanish, Portuguese, Russian, Polish, Japanese, Korean and Chinese by installing the corresponding language packs. Click here to search for how to install additional language packs.
Windows users can also install third party voices that are Microsoft SAPI 5 compliant. You can search for other voices here.