He is Abd Allaah bin Uthman bin Aamir bin Amr bibn Ka'b bin Sa'd bin Taym bin Marrah bin Ka'b bin Ibn Lu'ay bin Ghaalib al-Qurashi al-Taymi. His lineage meets with that of the Prophet (sallallaahu alayhi wasallam) at Marrah bin Ka'b. His kunyah is Abu Bakr, the word Bakr refers to a young camel, and the Arabs would be called by this name. He was given numerous titles all of which indicate his lofty, noble position. From them:
1. Al-Ateeq (The Delivered One): The Messenger (sallallaahu alayhi wasallam) said to Abu Bakr, "You are the delivered one (ateeq) of Allaah from the Fire" [Ibn Hibbaan, Saheeh], so he was named "Ateeq", and in the narration of Aai'shah who said: Abu Bakr entered upon the Messenger of Allaah (sallallaahu alayhi wasallam) who said to him, "Glad tidings for you are the Ateeq of Allaah from the Fire." [Al-Tirmidhi, Silsilah al-Sahihah, Saheeh.]
2. Al-Siddeeq (The Truthful, Believing One): He was given this title, as occurs in the hadeeth of Anas (radiallaahu anhu) that the Prophet (sallallaahu alayhi wasallam) was ascending Uhud and Abu Bakr, Umar and Uthmaan were all with him, and it shook (due to a tremor) so he said, "Be firm Uhud, for there is upon you a Prophet, a Siddeeq and two martyrs." [al-Bukhari, Virtues of the Companions]. Abu Bakr was named al-Siddeeq because of his abudnant tasdeeq (believing, attesting) of what the Messenger (sallallaahu alayhi wasallam) would inform of. The entire ummah is united upon this name for Abu Bakr, that he is al-Siddeeq and that he never hesitated at all in believing what the Messenger (sallallaahu alayhi wasallam) stated.
Al-Saahib (the Companion): This was given by Allaah, the Mighty and Majestic to Abu Bakr in the Qur'an, "If you help him (Muhammad) not (it does not matter), for Allah did indeed help him when the disbelievers drove him out, the second of two, when they both [Muhammad and Abu Bakr] were in the cave, and he said to his companion [Abu Bakr]: "Be not sad (or afraid), surely Allah is with us." Then Allah sent down His calmness upon him, and strengthened him with forces which you saw not, and made the word of those who disbelieved the lowermost, while it was the Word of Allah that became the uppermost, and Allah is All-Mighty, All-Wise." (At-Tawbah 9:40). Ibn Hajar al-Asqalani said regarding this verse, "The intent by "his companion" is Abu Bakr without any dispute, and the hadeeths about him being in the cave with him are many and well-known, and none besides him (Abu Bakr) shared with him in this virtue [al-Isabah Fi Tamyiz al-Sahabah 4/148].
4. Al-Atqaa (The Pious): It is mentioned in the books of tafseer that Surah al-Layl (92), and the verse, "And far removed from it (Hell) will be the pious, fearful one (al-atqaa)" (92:17) and what follows to the end of the Surah was revealed about Abu Bakr who would spent of his wealth in order to free some of the companions (who were slaves) such as Bilal bin Umayyah and Aamir bin Fuhayrah, doing that without seeking any recompense or thanks, but only seeking the face of Allaah. Al-Baghawai says that this verse refers to Abu Bakr according to the saying of all authorities.
5. Al-Awaah (the Fearful, Awestruck): This is mentioned by Ibn Sa'ad in al-Tabaqaat al-Kubraa that he was named al-Awaah, which indicates fear and awe of Allaah. Ibrahim al-Nakha'i said, "Abu Bakr used to be called al-Awaah due to his compassion and mercy." [al-Tabaqaat 3/171].
His father was Uthman bin Aamir bin Amar, called Abu Qahaafah, and he accepted Islam upon the conquest of Makkah. His mother was Salmaa bin Sakhar bin Amr bin Ka'b bin Sa'd bin Taym, Umm al-Khayr. She accepted Islam early on.
Abu Bakr al-Siddeeq (radiallaahu anhu) had four wives and from them six children, three male and three female. His wives were: Qutaylah bin Abd al-Uzzaa, mother of Abdullaah and Asmaa' and she was divorced in jaahiliyyah. Umm Roomaan bin Aamir bin Uwaymir, mother of Abd al-Rahmaan and Aa'ishah, she accepted Islam early on and migrated to Madinah, and she died 6H. Asmaa bin Umays bin Ma'bad al-Haarith, she was one of the very first emigrants, and she accepted Islam very early too. Her husband was martyred and Abu Bakr married her, and Muhammad was born through her, and many of the Companions narrated from him such as Umar, Abu Musa, Ibn Abbaas. Habeebah bin Khaarijah bin Zayd bin Abi Zuhayr, she was from the Ansar, and she gave birth to Umm Kulthum after the death of Abu Bakr.