You can command your computer in your mouth. This facility is available only for Win vista and Win 7.
Your computer must have connected with Microphone.
At first go to Control panel
After that Control Panel to Hardware and Sound
After that click on Sound
Click on Recording button
Click on Microphone which has Right Click image. ( Green color)
After that click on Configure button and set volume and speech recognized with your speech.
Click on Start speech Recognition
After click on Next. After you can see a logo like below
Click on above logo, you can see a dialogue box.
You can find this dialogue box off, Please turn on it
Now command your Computer it will work. If you face any problem Please see the start-Contorl Panel-Hardwear and Sound-Sound -Recording-Configure - Take Speech Tutorial.