Histograms - Question

[hasan_Z]

Greetings all,

Im new to photography, so I have the most basic questions.

What is a Histogram?
What are they used for?
Where can I read and learn about Histograms on the web?

Thanks in advance.

Hasan

[Nightcrawler]

Have a look here - http://www.luminous-landscape.com/tutorials/understanding-series/understanding-histograms.shtml