It's very easy to use, you can put your mouse anywhere within the graph area and drag in order to create shapes etc. You also have predefined graphs with lots of options which make it easier than other softwares I've tried so far! The interface is not very intuitive, but this should improve as more people use it. A few minor improvements regarding the "fill" functionality would be great. Also, when saving graphs for the next step, save them with the same name as the file you are working in (egโฆ