Group items tagged

Binary Octal Decimal Hexadecimal Glyph 0011 0000 060 48 30 0 0011 0001 061 49 31 1 0011 0010 062 50 32 2 0011 0011 063 51 33 3 0011 0100 064 52 34 4 0011 0101 065 53 35 5 0011 0110 066 54 36 6 0011 0111 067 55 37 7 0011 1000 070 56 38 8 0011 1001 071 57 39 9

In English, the term Arabic numerals can be ambiguous.

The numeral system came to be known to both the Persian mathematician Al-Khwarizmi, whose book On the Calculation with Hindu Numerals written about 825 in Arabic, and the Arab mathematician Al-Kindi, who wrote four volumes, "On the Use of the Indian Numerals"

The Arabic numerals are the ten digits (0, 1, 2, 3, 4, 5, 6, 7, 8, 9). They are descended from the Hindu-Arabic numeral system developed by Indian mathematicians, by which a sequence of digits such as "975" is read as a whole number. The Indian numerals were adopted by the Persian mathematicians in India, and passed on to the Arabs further west. The numerals were modified in shape as they were passed along; developing their moder

The reason that they are more commonly known as "Arabic numerals" in Europe and the Americas is that they were introduced to Europe in the tenth century from Arabs of North Africa.

Sources for Muhammad's life Prophet Muhammad at the Ka'ba, The Life of the Prophet Topkapi Palace Museum, Istanbul (Inv. 1222/123b), illustration by Nakkaş Osman [c. 1595]. Main articles: Historiography of early Islam and Historicity of Muhammad Being a highly influential historical figure, Muhammad's life, deeds, and thoughts have been debated by followers and opponents over the centuries, which makes a biography of him difficult to write.[14] The Qur'an Muslims regard the Qur'an as the primary source of knowledge about the historical Muhammad.[14] The Qur'an has a few allusions to Muhammad's life,[23]. The Qur'an responds "constantly and often candidly to Muhammad's changing historical circumstances and contains a wealth of hidden data."[14] Early biographies Next in importance are the historical works by writers of the third and fourth century of the Muslim era.[24] These include the traditional Muslim biographies of Muhammad and quotes attributed to him (the sira and hadith literature), which provide further information on Muhammad's life.[25] The earliest surviving written sira (biographies of Muhammad and quotes attributed to him) is Ibn Ishaq's Life of God's Messenger written ca. 767 (150 AH). The work is lost, but was used verbatim at great length by Ibn Hisham and Al-Tabari.[23][26] Another early source is the history of Muhammad's campaigns by al-Waqidi (death 207 of Muslim era), and the work of his secretary Ibn Sa'd al-Baghdadi (death 230 of Muslim era).[24] Many scholars accept the accuracy of the earliest biographies, though their accuracy is unascertainable.[23] Recent studies have led scholars to distinguish between the traditions touching legal matters and the purely historical ones. In the former sphere, traditions could have been subject to invention while in the latter sphere, aside from exceptional cases, the material may have been only subject to "tendential shaping".[27] In addition, the hadith collections are accounts of the verbal and physical traditions of Muhammad that date from several generations after his death.[28] Hadith compilations are records of the traditions or sayings of Muhammad. They might be defined as the biography of Muhammad perpetuated by the long memory of his community for their exemplification and obedience.[29] Western academics view the hadith collections with caution as accurate historical sources.[28] Scholars such as Madelung do not reject the narrations which have been complied in later periods, but judge them in the context of history and on the basis of their compatibility with the events and figures.[30] Finally, there are oral traditions. Although usually discounted by historians, oral tradition plays a major role in the Islamic understanding of Muhammad.[19] Non-Arabic sources The earliest Greek source for Muhammed is the 9th century writer Theophanes. The earliest Syriac source is the 7th century John bar Penkaye.[31]

withdrawal of clan protection implied that the blood revenge for his killing would not be exacted. Muhammad then visited Ta'if, another important city in Arabia, and tried to find a protector for himself there, but his effort failed and further brought him into physical danger.[14][71] Muhammad was forced to return to Mecca. A Meccan man named Mut'im b. Adi (and the protection of the tribe of Banu Nawfal) made it possible for him safely to re-enter his native city.[14][71] Many people were visiting Mecca on business or as pilgrims to the Kaaba. Muhammad took this opportunity to look for a new home for himself and his followers. After several unsuccessful negotiations, he found hope with some men from Yathrib (later called Medina).[14] The Arab population of Yathrib were familiar with monotheism because a Jewish community existed there.[14] Converts to Islam came from nearly all Arab tribes in Medina, such that by June of the subsequent year there were seventy-five Muslims coming to Mecca for pilgrimage and to meet Muhammad. Meeting him secretly by night, the group made what was known as the "Second Pledge of al-`Aqaba", or the "Pledge of War"[72] Following the pledges at Aqabah, Muhammad encouraged his followers to emigrate to Yathrib. As with the migration to Abyssinia, the Quraysh attempted to stop the emigration. However, almost all Muslims managed to leave

Last years in Mecca Road to Ta'if in the foreground, mountains of Ta'if in the background (Saudi Arabia). Muhammad's wife Khadijah and his uncle Abu Talib both died in 619, the year thus being known as the "year of sorrow." With the death of Abu Talib, the leadership of the Banu Hashim clan was passed to Abu Lahab, an inveterate enemy of Muhammad. Soon afterwards, Abu Lahab withdrew the clan's protection from Muhammad. This placed Muhammad in danger of death since the

The Black Death

The Black Death