Function Grapher is very easy to use. Although it may be too simple for graphing more complicated equations, it works extremely well for its intentions. Function Grapher is an excellent tool for someone who may not be able to afford a graphing calculator or just needs a quick and simple graph. It is also useful if a student wants to print out a graph to include in an assignment or a paper.
The different functions available in Function Grapher are very well defined and clearly available for students to access. It is also very easy to navigate around the graph and zoom in on specific sections of the graph.
I gave it four stars because I think it is a great site, but could use a few more advanced features.