Docs: What is Voice Typing in Google Docs?
Answer
There is a feature in Google Docs called “Voice Typing.”
YOU MUST USE THE GOOGLE CHROME BROWSER.
When you are logged in to your Google account, open a document in Google Docs. Under the "Tools" menu, scroll down to “Voice Typing.” A microphone icon will appear. Click on the microphone and start talking. The program may initially ask to access your computer’s microphone.
It is best to speak clearly and not too fast. You will probably need to edit your final document after using Voice Typing.
For further information see Google's webpage on the Voice Typing feature.