I am working on an asp.net mvc3 project and I have to display a histogram depending on the data coming from the action, can you offer me any javascript libraries that can be easy to use and make a good histogram, please, any syggestion !!
http://www.highcharts.com/ - great integration and nice appearance (free for non-profit)
http://www.jqplot.com/ - open source, good looking (free like in beer)
http://g.raphaeljs.com/ - another open source, well maintained
http://www.flotcharts.org/ - specifically for jQuery (if that's what you are using)
Basically, take a look at these and others, find one that looks good and easily connects to your existing architecture and roll.
If you just want to sort the data into baskets, see histogram.js .