A teleprompter is simply a computer, a monitor with an inverted/mirrored image, and a piece of glass.
The text the person is to read for their speech is programmed into the computer ahead of time and is "played back" by scrolling up the screen (like credits at the end of a movie).
If you looked at the computer monitor directly however, you would notice:
a) That it is laying down, face-up
b) All of the text is mirror-imaged (backwards)
A sheet of glass is then placed above the monitor at a 45 degree angle, reflecting the image to the speaker. Since the reflection of the glass "mirrors" (inverts) the image, it makes it readable.
The speed of playback is usually very carefully controlled by a human who adjusts the vertical scroll rate to keep pace with the speaker. For example, if he or she were to cough, causing a pause, you would not want the text to scroll off the top of the screen and be out of sync with what they were just saying.
Typically there are three teleprompters used; left, center, and right. This gives the appearance that the speaker is looking around the crowd, when in fact he or she is just picking another teleprompter to look at (and look personable to the crowd).
Here is a very helpful video showing how a teleprompter works. I find it extremely helpful. http://www.gowallaby.com/how-does-a-teleprompter-work
Free teleprompter/autocue service. CuePrompter is a free teleprompter/autocue service. Your browser works like a teleprompter -no extra software needed.
TelePrompter
Yes, Obama does use a teleprompter for most of his speeches.
It may be Autocue
The teleprompter was invented in 1950 by Fred Barton JR. The device was a created after the need to memorize large amounts of text in short periods of time arouse.
the whitehouse's teleprompter website
Teleprompter Operator
AUTOCUE is a device that displays words for people to read.ALSO Autocue is a UK based manufacturer of teleprompter systems. he company was founded in 1955 and patented its first teleprompter in 1962. This company is now in receivership.
The generic term is "teleprompter". There are several brands out there, but the Teleprompter brand was among the first, and the term is now coined to identify more of an item than a brand.
In a word, Yes.
My guess is Obama's teleprompter. http://baracksteleprompter.blogspot.com/