On reaching Makkah, the pilgrim first performs Umrah and thereafter he performs Hajj in the same ihraam; hence he will remain in the same ihraam till the end of Hajj.
Tamattu' - The pilgrim enters the state of ihraam with the intention of performing Umrah only.
After the completion of Umrah, this ihraam is removed and another ihraam is adopted before 8th Zul Hijjah with the intention of performing Hajj.
Ifraad - The pilgrim enters the state of ihraam with the intention of performing Hajj only. He does not combine it with Umrah.
After entering the ihraam, the pilgrim will remain under the restrictions until the end of Hajj.
Note: According to Sharee'ah, ihraam is to enter into a state in which certain halaal (lawful) things become prohibited for a person e.g use of perfume, trimming or shaving hair from the body, etc.
This is done by wearing two sheets, making niyyah of Hajj/Umrah and reciting talbiyah. (The women will remain in their normal clothing).
The two sheets worn by the pilgrim are also called ihraam. Some people think that once these sheets are put on, they cannot be taken off. This is not so.
By taking them off, the pilgrim does not come out of the state of ihraam. He will come out of the state of ihraam only when he completes all the essential rites of Hajj/Umrah.
Aboo Hurayrah (may Allah be pleased with him) reports that Rasoolullah (peace be upon him) said,
"Whoever performs Hajj for the sake of pleasing Allah and therein utters no word of evil, nor commits any evil deed, shall return from it as free from sin like as the day on which his mother gave birth to him." (Bukhaari,Muslim)
Aa'ishah (may Allah be pleased with her) reports that Rasoolullah (peace bu upon him) said,
"There is no day in which Allah sets free more souls from the fire of Hell than on the day of Arafaat. And on that day Allah draws near to the earth and by way of exhibition His pride remarks to the angels:'What is the desire of these servants of mine'." (Muslim)