Available cross-platform for Windows, Linux and Mac, its primary function is the visualization of mathematical data and functions.
Gnuplot is one of the best-established graphing tools, popular among intermediate and advanced users. As an economist, it's important to make sure your graphs are looking as good as possible, as they are essential for winning over and keeping the attention of your audience. Other software exists for the singular purpose of configuring your diagrams, including many which are open-source and hence freely available.
The standard graphs produced by software such as Excel or SPSS can convey the required information, but tend to lack style as these tools have limited customisation options.
A great way to make your presentations or papers slick and memorable is to improve your graphs and diagrams.