Zamzam water is the best and noblest of all waters, the highest in status, the dearest to people, the most precious and valuable to them. For more, please see the detailed answer.

The 10 Companions who were promised Jannah by Prophet Muhammad (peace and blessings of Allah be upon him) are: Abu Bakr Al-Siddiq, Umar ibn al-Khattab, ‘Uthman ibn Affan, ‘Ali ibn Abi Talib, Talhah ibn ‘Ubaydullah, al-Zubayr ibn al’-Awwam, ‘Abd al-Rahman ibn ‘Awf, Sa`d ibn Abi Waqqas, Sa’id ibn Zayd, and Abu `Ubaydah ibn al-Jarrah

The Prophet (peace and blessings of Allah be upon him) said concerning the water of Zamzam, “It is a blessing, and it is food that satisfies.” (in one narration, “and a cure for the sick.”) When you drink Zamzam water, you should face the Ka`bah, say Bismillah, pause to take a breath three times, drink your fill, praise Allah after you finish, and sit whilst drinking.