Tawhid: (Arabic: توحيد tawḥīd "doctrine of Oneness [of God ]"; also transliterated Tawheed and Tauheed) is the concept of monotheism in Islam. It holds God (Arabic: Allaah) is one (wāḥid) and unique (ahad).

Aqidah: (sometimes spelled Aqeedah, ʿAqīdah or ʿAqīda) (Arabic: عقيدة plural عقائد ʿaqā'id‎) is an Islamic term meaning creed. Any religious belief system, or creed, can be considered an example of aqidah. However this term has taken a significant technical usage in Muslim history and theology, denoting those matters over which Muslims hold conviction.