Cosma is a visualization tool that works on Windows and Mac operating systems. It is available in French and English. Its input are linked markdown text files and it creates an HTML network visualization of the files. There are many options to customize the visualization. The HTML visualization can be exported and shared unlike others tools in which only the static image of the visualization is share. This means that the data and the tools to explore it are shared simultaneously. Cosma is free to download, use and modify.