Aqeeda (or aqida) (Arabic: عقيدة) is Islamic creed. It is a branch of Islamic studies describing the beliefs of Islam.
Islam, Iman, Ihsan
From the hadith of Jibreel (عليه السلام) we learn basic concepts about Islam, Iman, and Ihsan.
In terms of their sciences, fiqh pertains to Islam, aqida pertains to Iman, and tasawwuf pertains to Ihsan.
Ash’ari Fundamentals | A Brief Critique on Ibn Taymiyyah’s Tawhid – Refutation of the 3 tawhids