Is there any difference between Sunnah, mustahabb and nafil?

What is the difference between Sunnah and Nafel? and Sunnah and Musthab?

Praise be to Allah, and blessings and peace be upon the Messenger of Allah:

The majority of scholars of Usool al-Fiqh say that there is no difference between Sunnah, mustahabb, tatawwu’ (voluntary actions) and nafil. But the Hanafis say something different. They regard mandoob (recommended) as being of the same status as nafil, and they differentiate between Sunnah and nafil, regarding Sunnah as being higher in status.