sentences:  Older QtiPlot versions up to 0.9.8.9 were released under the terms of the GNU General Public License (GPL) and are available also as binaries for Linux distribution repositories as well as for Windows.Starting with version 0.9.9 the source code is not available from the author anymore.Compiled binaries are available for Microsoft Windows, several Linux distributions and Mac OS X; downloading binaries from the author's website requires purchase of an annual maintenance contract.