How to make a program that analyzes screen and makes decisions off what the program sees?q

[brokenbot]

How can I read the screen/gui and make a program be reactive to what it "sees"?

[webJose]

Research about UI Automation.

[andywestken]

Are you wanting to find the windows and communicate with them progammatically, like some test test tools do?

Or are you interested in screen scaping?
http://en.wikipedia.org/wiki/Screenscraping#Screen_scraping