Browse the Speech API 5.3 SDK Documentation Online

You can download the full Windows SDK from here, but if you just want to read the documentation for SAPI, you can do so from this link.

To browse the Managed Speech API documentation, here are the links to the various namespaces:

System.Speech.AudioFormat
System.Speech.Recognition
System.Speech.Recognition.SrgsGrammar
System.Speech.Synthesis
System.Speech.Synthesis.TtsEngine