- Natural number (Wikipedia)
In mathematics, the natural numbers are the numbers 1, 2, 3, etc., possibly including 0 as well. Some definitions, including the standard ISO 80000-2, begin the natural numbers with 0, corresponding to the non-negative integers 0, 1, 2, 3, …, whereas others start with 1, corresponding to the positive integers 1, 2, 3, … Texts that exclude zero from the natural numbers sometimes refer to the natural numbers together with zero as the whole numbers, while in other writings, that term is used instead for the integers (including negative integers). In common language, particularly in primary school education, natural numbers may be called counting numbers to intuitively exclude the negative integers and zero, and also to contrast the discreteness of counting to the continuity of measurement—a hallmark characteristic of real numbers.
- Hadith (Wikipedia)
Ḥadīth (/ˈhædɪθ/ or /hɑːˈdiːθ/; Arabic: حديث, ḥadīṯ, Arabic pronunciation: [ħadiːθ]; pl. aḥādīth, أحاديث, ʾaḥādīṯ, Arabic pronunciation: [ʔaħaːdiːθ], lit. ’talk’ or ‘discourse’) or Athar (Arabic: أثر, ʾAṯar, lit. ‘remnant’ or ’effect’) refers to what most Muslims and the mainstream schools of Islamic thought believe to be a record of the words, actions, and the silent approval of the Islamic prophet Muhammad as transmitted through chains of narrators. In other words, the ḥadīth are attributed reports about what Muhammad said and did (see: Oral tradition).