This applet generates such classics as the Mandelbrot Set and the Sierpinski
triangle using iterations.
There are two main panels: the left one is used for the main fractal (e.g. the Mandelbrot set), and the right one is used for its Julia set.
Select fractal from the pull down menu in the middle. Currently you can choose between three different fractals: the Mandelbrot Set, the Sierpinski Triangle, and "Dragon" which looks like a double Mandelbrot set.
Press "Generate" to draw fractal. You can specify the maximum number of iterations using the edit field right next to the "Generate" button.
Click anywhere on the Mandelbrot Set to generate the corresponding Julia Set. The C used in the calculation of the Julia Set is shown in the middle column. You can also select a specific Julia Set by changing the C manually and clicking "Generate" in the right side panel.
To zoom in, simply left-click and drag for the region to zoom in on.
Right-click to zoom out. You can also enter the coordinates of the region you wish to view using the fields at the bottom.
If "Show Julia" is checked, then the Julia Set for the point at which your mouse is at will be shown on a little panel on top of the Mandelbrot Set. Unfortunately, this feature is still very buggy when used with a browser.