Windows Speech Recognition

To switch on/off Speech Recognition, press Windows key + Control + S.
If it is the first time you have used the feature, it will get you to set up your microphone and start learning your voice. I would always recommend using a headset when using speech recognition (especially if you also use a screen reader).
It sounds very powerful to use speech recognition so you don’t have to type or operate the keyboard or mouse. But it doesn’t always get things right, and you need to verify everything that you dictate. Also, there is a set of commands to learn, same as learning a set of keyboard shortcuts. Having said that it will get better over time, as it learns your voice and you correct its mistakes, so be patient.
Follow this link for a list of Windows Speech Recognition commands.