What do ritual impurity/hadath and ritual purification/taharah from hadath mean? The short answer is…
Ritual impurity means the state of spiritual impurity which is considered to have caused by not being in the state of minor ablution and being in the state of major impurity (janabah), in religious literature. In religious books, this is identified with the concept of hadath (Bukhari, Wudu, 2, Maydani, al-Lubab, I, 5).
Hadath is divided into two types as minor hadath and major hadath. Ritual impurities such as being in the state of major impurity (janabah) and being in menstruation and postnatal period are the states of major hadath and the ritual impurity which requires minor ablution (wudu) is minor hadath (Maydani, al-Lubab, I, 5).
Major ritual impurity is cleaned with ghusl while minor ritual impurity is cleaned with minor ablution. One can be cleaned from both conditions with tayammum in the event that there is no water or one cannot use it due to an excuse although it exists (Kasani, Bada’i, I, 44).
Source: Presidency Of Religious Affairs The Turkey, High Board of Religious Affairs FATWAS