This site contains 29761 parsed manpages from sections 1 and 8 found in Ubuntu's manpage repository. A lot of heuristics were used to extract the arguments of each program, and there are errors here and there, especially in manpages that have a non-standard layout.
It is written in Python and uses bashlex, a bit of NLTK (to find the interesting parts of the manpage), a little d3.js (for the connecting lines graphic) and Flask. It is served with uwsgi and nginx. Source code is available on github.
My name is Idan Kamara and you can contact me at idan at explainshell dot com for any questions or suggestions.