Using Speech Recognition to Enter Text
Speech recognition is still in its infancy, and Office's implementation only underscores that fact. Speech recognition can be a godsend to those who are physically challenged; however, text input using dictation rates as little more than a novelty to serious Office users. Voice Command mode doesn't fare much better.
Before you even attempt speech recognition, make sure you have the following:
A PC running at 300MHz or faster (Microsoft's recommendation). In tests run for this book, corn grew faster than dictation on a 500MHz machine.
At least 96MB of memory.
A high-quality microphone that comfortably sits within an inch of your mouth.
Start using speech recognition by choosing Tools, Speech. You will go through a 15-minute "training" exercise, where the speech recognition software learns to recognize the words you speak (see Figure 4.8). Training is required even if you're only going to use speech recognition for commands. When you finish the training, Office connects to the Web and runs a video.
Figure 4.8. Start by training the Speech Recognition system to understand words as you speak them.
When Speech Recognition is activated (choose Tools, Speech), a free-floating bar called the Language bar appears in the upper- right area of the screen.
Note
The Language bar might look like a plain-vanilla Office toolbar, but it isn't. You can't hide it or make it appear by choosing Tools, Customize, Toolbars. It won't dock. It's available to all of Windows, so the toolbar doesn't travel with an application's window when it's minimized. To get rid of the bar, right-click the left or right ends, and choose Close the Language bar.
Clicking Voice Command on the Language bar sets up voice recognition so you can choose menu items: File <pause, pause, pause> Open <pause, pause, pause> will reliably bring up the Open dialog box, for example. After the dialog box appears, you can navigate to a greater or lesser extent by using the names of tabs on tabbed dialog boxes, or drop-down lists. For example, if you want to open the fifth document in your My Documents folder, you would say: File <pause, pause, pause>, Open <pause, pause, pause>, Down <pause, and so on>, Down, Down, Down, Open. (Assuming all your commands were understood, and you didn't end up opening the Views list, for example.)
Note
On a 500MHz PC, we could disconnect the mouse from the back of the PC, open the mouse up, blow off the ball, put it back together, reconnect it, and then use the mouse to open the fifth document in the My Documents folder in about the same amount of time that it took to use Voice Command. And the mouse would do it reliably, whereas the Voice Command sequence frequently sent us off into Office never-never land.
Choosing Dictation on the Language bar enables you to dictate into the document. Microsoft claims an initial recognition rate of 85%–90%, providing you use a high-quality microphone, you're working in a dead-silent room, and you consistently keep the microphone in the same location close to your mouth. Our tests didn't measure up to that claim, but your results might vary.
Tip from 
Do the math. If you commonly put 2,000 characters in a typical single-page business letter, and your error rate is 15%–20%, you'll have to change 300–400 characters on that page before it's usable. Right-click spell checking and grammar correction help speed up the process, but using the built-in Word tools don't help "train" the voice recognition system.
Microsoft claims a recognition rate of 95% if you devote a sufficient amount of time to "training"—and you can go back to training at any time. Every time you use the Correction tool on the Language bar, you're helping train the speech recognition system, as well.
Tip from 
The most important fact a typical Office user needs to know about speech recognition is how to remove it. Go into Control Panel (Start, Settings, Control Panel), double-click Add/Remove Programs. Choose Microsoft Office, click Change. Choose Add or Remove Features. Pull down the list under Office Shared Features and under Alternative User Input, turn the icon in front of Speech to a big red X (Unavailable). Click Update, and speech recognition goes away.