Taharat From Hadas

There are two kinds of taharat from hadas:

1 - Performance of an ablution by a person who does not have an ablution.
2 - Performance of a ghusl by a person who does not have a ghusl.

Wudu means ablution; tawaddi means to perform an ablution; ghasl means to wash something; ightisal means to perform a ghusl ablution, and ghusl means the ablution of ghusl (in Arabic). He who does not have an ablution is called muhdis. He who does not have a ghusl ablution is called junub.

It is written in the book Halabi-yi saghir: "There are fards [1], sunnats [2], adabs [3], and forbidden things in an wudu (ablution). If a person performs salat without an ablution though he does not have a good excuse for doing so and though he knows that he does not have an ablution, he becomes a disbeliever. He who loses his ablution while performing salat, performs the salam (saying "Assalam-u alaikum wa rahmat-ullah" in finishing the prayer) to one side right away and stops his salat. Re-making an ablution before the prescribed time period is over, he begins the salat again. " In Maliki madhhab [4], his salat will not be nullified and he will become owner of an excuse in that moment.

[1] fard: an act or thing that is commanded by Allahu ta'ala in the Qur'an al-kerim. Fard (or fard) means (any behaviour or thought or belief which is) obligatory. Islam's open commandments are called fard (pl. faraid).
[2] sunna: act, thing that was, though not commanded by Allahu ta'ala, done and liked by the Prophet ('alaihi 's-salam) as an 'ibada (there is thawab if done, but no sin if omitted, yet it causes sin if continually omitted and disbelief if disliked; the Sunna; i) (with fard) all the sunnas as a whole; ii) (with the Book or Qur'an al-kerim) the Hadith ash-sharif; iii) (alone) fiqh, Islam.
[3] Adab: there is a special adab in doing everything. The adab of doing something means to follow the conditions necessary for doing it in the best way.
[4] madhhab: all of what a profound 'alim of (especially) Fiqh (usually one of the four-Hanafi, Shafi'i, Maliki, Hanbali) or iman (one of the two, namely Ash-ari, Maturidi) communicated.