function grapher is an easy-to-use software to create 2d, 2.5d, 3d function graphs, animations and table graphs. 2d features: explicit, implicit, parametric, and in equation; cartesian and polar coordinate systems; curve and animation; graph of inverse function and derivative function; parity; maximum, minimum, and inflexion; integration; root; the length of curve; tangent and normal; curvature circle; intersection; line plot; scatter plot; stem plot; step plot; curve smoothing. 3d features: cartesian, cylindrical, and spherical coordinate systems; 3d curve and surface; animation; 3d surface based on table data; surface by rotation; material and light. ability to create color map, contour plot and vector plot. ability to move, zoom in, zoom out and rotate graphs. ability to save graphs as pgp file or bmp file. ability to save animation as avi file.