Mac Basics: Dictation lets you speak text instead of typing
Getting started with Dictation  Use these steps to turn
Dictation on or off:    1. From the Apple menu, choose System
Preferences.   2. From the View menu, choose Dictation & Speech
to view Dictation preferences.   3. Click On to enable Dication,
or Off to disable it.  You can also choose a shortcut key,
change your language, and select a microphone from Dictation
preferences.  If your computer or display doesn't have a built-
in microphone, you can connect an external microphone to use
Dictation.  Using Dictation in an app  You can speak the text
you want to enter in a text field, like a TextEdit or Pages
document.  Use these steps to start dictating:    1. Click a
text field or document window where you want to start typing.
2. Press the fn (Function) key twice, or choose Edit > Start
Dictation.   3. Dictate (speak) what you want your Mac to type.
4. When finished, click Done or press the fn key again. Your
spoken words then appear in the text