These questions are the same; they're by the same author:
- https://islam.stackexchange.com/questions/33720/what-are-the-similarities-differences-between-the-four-madhabs-charts
- https://islam.stackexchange.com/questions/35293/what-are-basic-osol-al-fiqh-differences-similarities-between-the-4-existing
The first one is currently an open, unanswered question. The second one currently has a good-quality answer, but was closed.