How does a weather satellite function?

i need some material to knew the working of weather satellite.
how it works?
what type of technologies it used?

reply asap
best regards

run down a book by Ulaby on remots sensing and radiometers. That may get you started.

Added after 22 seconds:

http://en.wikipedia.org/wiki/Weather_satellite

there is one website
www.howstuffworks.com
search on that

Abhishekabs