Ghusl is an Arabic term referring to washing of the entire body with water. Ghusl in Islam means the bathing of the entire body with water. The full body wash becomes mandatory for any adult Muslim (Male and Female) after having sexual intercourse, any sexual discharge, completion of the menstrual cycle, giving birth, and death by natural causes.
Islam also recommends (Mustahab) the performance of the Ghusl before the Friday Salah and 2 Eid prayers, before entering the Ihram, in preparation for Hajj and after formally reverting to Islam. Ghusl should not be confused with wudhu (ablution), a partial ablution that Muslims perform before salah.  
Ghusl is compulsory upon us by one of three matters:
1) Either by ejaculation, even (if this happened) without sexual relations by wet dream in sleep. Sahih Al Mulsim 608
2) By (having) sexual relations, even (if this happens) without ejaculating. Sahih Al Bhukari 291, Sahih Al Muslim, no. 526
3) By emission of semenby having sexual relations and ejaculating. Sahih Al Bhukari Vol 1: 269
It is upon this individual to repeat his prayers that he prayed before he made the Ghusl, because he has with him, in reality, something by way of neglect. And it is obligatory upon him to ask the people of knowledge, and to repeat all of these prayers, meaning, he does not pray each prayer along with its equivalent, rather; he prayers them all together. Shaykh Muhammad bin Saalih al-`Uthaymeen Liqaa-aat-ul-Baab-il-Maftooh. Vol 1
Allah (Glory be to Him) Says in the Qur’an: O you who believe! When you prepare for prayer (Salah) wash your faces and your hands (and arms) to the elbows; rub your heads (with water); and (wash) your feet to the ankles. If you are in a state of ceremonial impurity (post menstruation, post sexual intercourse, etc.) bathe your whole body. But if you are ill or on a journey or one of you cometh from offices of nature or ye have been in contact with women and ye find no water then take for yourselves clean sand or earth and rub therewith your faces and hands. Allah doth not wish to place you in a difficulty but to make you clean and to complete His favor to you that ye may be grateful. Qur’an.Surah Maidah 5:6
Ghusl may be wajib (obligatory) or it may be Sunnah and Mustahab. The scholars (may Allah have mercy on them) have described all cases, and their comments may be divided into three categories:
1 – Cases in which Ghusl is required (Compulsory)
(i) Emission of Mani (semen) even if it is not through intercourse.
The basic principle concerning that is the hadeeth of Abu Sa’eed al-Khudri (R) according to which the Prophet Muhammad (May Allah honour Him and grant Him peace) said: “Water is for water (i.e., Ghusl must be done when semen is emitted).” Sahih Al Muslim 343
(ii) Meeting of the two circumcised parts when the tip of the penis disappears completely in the vagina, even if no ejaculation takes place.
When the two “circumcised parts” meet, which is penetration, i.e. intercourse – even if there is no ejaculation – because the Prophetﷺ said: “When the two circumcised parts meet and the tip of the penis disappears, Ghusl becomes obligatory, whether ejaculation takes place or not.” Saheeh Sunan Abi Dawood, 209
(iii) And (iv) Menstruation and Nifaas (post partum bleeding)
“They ask you concerning menstruation. Say: that is an Adha (a harmful thing for a husband to have a sexual intercourse with his wife while she is having her menses), therefore, keep away from women during menses and go not unto them till they are purified (from menses and have taken a bath). And when they have purified themselves, then go in unto them as Allah (Glory be to Him) has ordained for you” Qur’an.Surah Baqarah 2:222. And because the Prophet(May Allah honour Him and grant Him peace) said to Faatimah bint Hubaysh (R): "When your period starts, stop praying, and when your period ends, perform Ghusl thenstart praying again." Sahih Al Bukhari, Fath, 309
2 – Cases in which Ghusl is not required but it is Mustahab (recommended)
(i) For some acts of worship, such as doing Ghusl when entering ihraam.
The Prophet (peace and blessings of Allah be upon him) did Ghusl before changing into his ihram garments. Narrated by al-Tirmidhi, 830. It is mustahab to do Ghusl for tawaaf al-ziyaarah and tawaaf al-wadaa’ (farewell tawaaf). When Ibn ‘Umar entered Makkah he would do Ghusl, and he said that the Prophet (peace and blessings of Allah (Glory be to Him) be upon him) used to do that. Sahih Al Bhukari 1478 and Sahih Al Muslim 1259
(ii) Ghusl for the deceased (apart from a martyr slain in battle).
The majority of scholars are of the view that death is one of the things that make Ghusl obligatory, because the Prophet (May Allah honour Him and grant Him peace) said to the women when his daughter died: “Wash her three times or five or more than that.” Sahih Al Bhukari 1253 and Sahih Al Muslim 939
(iii) Ghusl after washing the deceased.
The scholars differed concerning this, based on their differences about the hadeeth that was narrated concerning it. It was narrated from Abu Hurayrah (may Allah be pleased with him) that the Prophetﷺ said: “Whoever has washed a dead person, let him do Ghusl.” Narrated by Musnad Ahmad 2/454, Abu Dawood 3161 and al-Tirmidhi 993, who said it is a hasan hadeeth. Imam Ahmad said in Masaa’il Ahmad by Abu Dawood 309.
(iv) Ghusl on Fridays
It is Sunnah according to the majority, and some regarded it as obligatory.
The correct view is that which was favoured by Shaykh al-Islam Ibn Taymiyah in al-Fataawa al-Kubra (5/307): It is obligatory to do Ghusl on Fridays for one who is sweaty or has an odour that may offend others.
(v) When a kaafir becomes Muslim
Narrated by Abu Hurayrah (R) that Thumaamah ibn Athaal (may Allah be pleased with him) became Muslim, and the Prophet (May Allah honour Him and grant Him peace) said: “Take him to the garden of Banu So and so and tell him to do Ghusl.” And it was narrated that when Qays ibn ‘Aasim (R) became Muslim, the Prophet(May Allah honour Him and grant Him peace) be upon him) told him to do Ghusl with water and lotus leaves. And in most cases the new Muslim will not be free of janaabah, so Ghusl is required for that reason. Tirmidhi 605, Abu dawud 355 With regard to circumcision, it is obligatory for men but only recommended for women. However, it could be delayed until Islam is firmly established in their hearts, lest it should induce their aversion to Islam.  
The liquid is a substance well known as Al-Mathi and it is a white, sticky fluid, which is emitted (Released) after sexual arousal, or thoughts of sexual intercourse ect.It should be washed, if it gets on the clothes, but Ghusl is not required except due to the emission of Al-Mani (Sperm) at the time of ejaculation. Al-Mani is a well known yellowish fluid, and the difference between them is clear, both regarding colour and ruling.
Other than urine, there are basically three types of discharges that are released from one’s private organs:
If only Wadi or Madhi is released, one does not require a ‘Ghusl’ or full bath to purify himself; he must wash his private parts and the part of his clothes or body where the ‘wadi’ or ‘madhi’ has touched, do the wudu, and he would be available for prayer.
If Mani is released, then it become obligatory to perform a ‘Ghusl’ or full bath to purify oneself. 
Narrated by Umm Sulaym (R)
Umm Sulaym asked the Messenger of Allah (May Allah honour Him and grant Him peace) about a woman who sees in a dream what a man sees (sexual or wet dream). The Messenger of Allah (saws) said: ‘In case a woman experiences a ‘wet-dream’, she must perform a ‘Ghusl’.’ Umm Sulaym (R) said: ‘I was bashful on account of that and said: ‘Does a woman get discharge?’ Upon this the Messenger of Allah (May Allah honour Him and grant Him peace) said: ‘Yes (it does happen), otherwise how can (a child) resemble its mother? The man's sexual discharge is thick and white, and the (sexual) discharge of woman is thin and yellow ; so the resemblance comes from the one whose genes prevail or dominate.’ Sahih Al Muslim 608
In light of the above authentic narration, it is evident that a woman too can experience a full sexual discharge or ‘Mani’.
There is a difference between the “water” of the man and that of the woman. The man’s water is white and thick, and the woman’s water is yellow and thin.
It was narrated that Umm Salamah (R) said: The Prophet (May Allah honour Him and grant Him peace) said: “The water of the man is thick and white, and the water of the woman is thin and yellow.” Sahih Al Muslim, 311 
The Ghusl for men and women is as follows:
1. Intention inside ones heart not verbal.
All parts of the body should be rubbed with the hand so as to ensure that water has reached all parts of the body, and that no portion is left dry.
If the hair of the head is not plaited, it is compulsory to wet all the hair up to the very base. If a single hair is left dry, Ghusl will not be valid. If the hair of a woman is plaited, she is excused from loosening her plaited hair, but it is compulsory for her to wet the base of each and every hair. If one fails to do this then the Ghusl will not be valid.
"Janabat" is a ritual impurity caused by the discharge of semen or by sexual intercourse; and the person on whom ghusl janabat becomes wajib is known as "junub" in Arabic. The Qur'an says: O you who believe! Do not go near prayers (salat) when you are... junub until you have washed yourselves. Qur’an .Surah Nisa 4:43O you who believe! When you stand up for prayers (salat), . . . if you are junub, then purify (yourselves). Qur’an .Surah Ma’idah 5:6
The Causes Of Ghusl Janabat
There are two causes of Janabat:
1. Discharge of semen.It does not make any difference whether this discharge is while awake or in a wet-dream, slight or profuse, intentionally or otherwise, in lawful way or unlawful (e.g., masturbation). In all these cases Ghusl janabat becomes obligatory (wajib).
If a liquid comes out from a man and he does not know whether or not it is semen, then he should look for the following three signs: (1) emission with passion; (2) spurting discharge; (3) feeling relaxed after the discharge. If these signs are found together on him, then he should consider the liquid as semen, otherwise not.
If a secretion is discharged from a woman, then it is precautionary wajib for her to do Ghusl janabat provided it came with sexual passion and she felt relaxed after it. But if the secretion comes without the sexual passion or without the feeling of relaxation after the discharge, then it is not najis and therefore Ghusl is not wajib upon her.
2. Sexual Intercourse.It does not make any difference whether the intercourse was lawful or unlawful, and with or without discharge of semen. In Islamic laws, sexual intercourse is defined as the penetration of the glands into the vagina or anus of the woman. That is, for Ghusl Janabat to become wajib it is not necessary that full penetration or discharge of semen should take place. In case of sexual intercourse, Ghusl Janabat becomes wajib on both the man and the woman.
One type of blood which is seen by women is called istihaza and a woman in that state is called mustahaza. Istihaza is usually yellowish and cold and is emitted without gush or irritation and is also not thick. It is, however, possible that at times the color of the blood may be red or dark, and it may also be warm and thick and may be issued with gush and irritation.
There are three kinds of Istihaza:
I. Little Blood (Qalila)
If the blood remains on the surface of the wool or pad etc., (placed by a woman on her private part) but does not penetrate into it, the istihaza is called qalila. (In the case of little istihaza the a woman should perform separate Wudhu for every prayer)
II. Medium Blood (Mutawassita)
If the blood penetrates into the cotton (or pad etc.), even partially, but does not soak the cloth tied on the outer side, the istihaza is called mutawassita. (In the case of Mutawassita, it is an obligatory precaution for a woman to make one Ghusl everyday for her daily prayers)
III. Excessive Blood (Kathira)
If the blood penetrates through the cotton, soaking it and the cloth (etc.) around it, the istihaza is called kathira. (In the case of excessive bleeding the woman should do one Ghusl for Fajr prayers, one for Zuhr and Asr prayers and once again for Maghrib and Isha prayers. She should offer Asr prayers immediately after Zuhr prayers and if she allowed any lapse of time between them, she should do Ghusl again for Asr prayers. Similarly if she keeps any time gap between Maghrib and Isha prayers, she should do Ghusl again for Isha prayers.)
What has been mentioned above are the wajib acts of Ghusl; here we shall explain the things which are recommendable (mustahab, sunnat) during the Ghusl. These recommendable acts are five: