Gnuplot is not new (more than 15 years old)., but it is continuously updated/upgraded. Not only displays variously formatted pictures of experimental or tabulated data, but accepts your own functions, in 1, 2 or more dimensions. A lot of supported graphic formats for hard copies, including png, jpeg, PostScript, and many more. See for yourself. By the way: its free and works under Unix, Linux, Windows and Mac.