GnuPlot - Gnuplot is a portable command-line driven interactive data and function plotting utility.
Duolingo - Duolingo is a free language learning app for iOS, Windows and Android devices. The app makes learning a new language fun by breaking learning into small lessons where you can earn points and move up through the levels. Read more about Duolingo.
LabPlot - LabPlot is a KDE-application for interactive graphing and analysis of scientific data.
Memrise - Learn a new language with games, humorous chatbots and over 30,000 native speaker videos.
Matplotlib - matplotlib is a python 2D plotting library which produces publication quality figures in a variety...
Busuu - Join the global language learning community, take language courses to practice reading, writing, listening and speaking and learn a new language. Learn English with busuu's .