About the visualization of graphs in the web talked 
here , inspired by 
this article.
Under the cat review of JavaScript libraries for drawing graphs, charts and other beauty.
TufteGraph
Uses jQuery.
Website: 
xaviershay.github.com/tufte-graph')

dygraphs
dygraphs is an open source JavaScript library for drawing time series.

Website: 
www.danvk.org/dygraphsDemo: 
www.danvk.org/dygraphs/testsHighcharts
About Highcharts wrote 
here .

Website: 
www.highcharts.comgRaphaël
gRaphaël is an open source library that allows you to draw pie, bar, line or dot charts diagrams.

Website: 
g.raphaeljs.comMilkChart
MilkChart - MooTools library for converting tables to charts.

Uses and supports the following chart types:
* Column
* Bar
* Line
* Scatter
* Pie
Website: 
code.google.com/p/milkchartVisualize
Visualize is a jQuery plugin that converts tables to charts using the canvas tag.

The use is very simple (allows you to draw line, pie, bar or area charts):
$ ('table'). visualize ();
Website: 
http://www.filamentgroup.com/InfoVis
A library for drawing treemaps, radial layouts, bar charths, pie charts, and other canvas-based charts.

Website: 
thejit.orgjqPlot
jqPlot - jQuery plugin, can draw line and bar charts.

Website: 
www.jqplot.comProtovis
Protovis - JavaScript library, uses canvas.

Website: 
vis.stanford.edu/protovisWhich library is better, which one is not - it is difficult to say, I myself use the 
asp.net chart control for such cases, although many of these are very much nothing :)
The thought is enough for now. If this topic is interesting, I can continue a series of posts about data visualization on the web.
Thanks for attention!