Description: Duolingo is a free language-learning platform that offers over 100 total courses across more than 30 languages. The bite-sized lessons make it easy to learn a new language through fun, quick activities on your phone, tablet, or computer.
Type: software
Pricing: Freemium
Description: NumeRe is an open-source numerical computing environment and programming language for numerical analysis, visualization, and statistics. It is similar to MATLAB and Python-based scientific computing packages, providing fast matrix operations, plotting tools, statistics functionality, and interfaces to C/C++, Fortran, and Julia.
Type: software
Pricing: Open Source