8

8 (eight) is the natural number following 7 and preceding 9.

English eight, from Old English eahta, æhta,

Evolution of the Arabic digit

This section needs additional citations for verification. Please help improve this article by adding citations to reliable sources in this section. Unsourced material may be challenged and removed. (May 2024) (Learn how and when to remove this message)

The modern digit 8, like all modern Arabic numerals other than zero, originates with the Brahmi numerals. The Brahmi digit for eight by the 1st century was written in one stroke as a curve └┐ looking like an uppercase H with the bottom half of the left line and the upper half of the right line removed. However, the digit for eight used in India in the early centuries of the Common Era developed considerable graphic variation, and in some cases took the shape of a single wedge, which was adopted into the Perso-Arabic tradition as ٨ (and also gave rise to the later Devanagari form ८); the alternative curved glyph also existed as a variant in Perso-Arabic tradition, where it came to look similar to our digit 5.^{[year needed]}

The digits as used in Al-Andalus by the 10th century were a distinctive western variant of the glyphs used in the Arabic-speaking world, known as ghubār numerals (ghubār translating to "sand table"). In these digits, the line of the 5-like glyph used in Indian manuscripts for eight came to be formed in ghubār as a closed loop, which was the 8-shape that became adopted into European use in the 10th century.^[3]

Just as in most modern typefaces, in typefaces with text figures the character for the digit 8 usually has an ascender, as, for example, in .

The

8 is a

The lie group E₈ is one of 5 exceptional lie groups.^[16][17] The order of the smallest non-abelian group whose subgroups are all normal is 8.^{[citation needed]}

• In nuclear physics, the second magic number.^[18]

• The most stable allotrope of a sulfur molecule is made of eight sulfur atoms arranged in a rhombic form.^[19]

• A byte is eight bits.^[20]

• Sailors and civilians alike from the 1500s onward referred to evenly divided parts of the Spanish dollar as "pieces of eight", or "bits".

• The octagram Rub el Hizb is often used in Islamic symbology.

• The number eight is considered to be a
  lucky number in Chinese culture because it sounds like the word meaning to generate wealth (發(T) 发(S); Pinyin: fā). Property with the number 8 may be valued greatly by Chinese. For example, a Hong Kong number plate with the number 8 was sold for $640,000.^[23] The opening ceremony of the Summer Olympics in Beijing started at 8 seconds and 8 minutes past 8 pm (local time) on 8 August 2008.^[24]
• In Pythagorean numerology the number 8 represents victory, prosperity and overcoming.
• Eight (八, hachi, ya) is also considered a lucky number in Japan, but the reason is different from that in Chinese culture.^[25] Eight gives an idea of growing prosperous, because the letter (八) broadens gradually.
• The Japanese thought of eight (や, ya) as a holy number in the ancient times. The reason is less well-understood, but it is thought that it is related to the fact they used eight to express large numbers vaguely such as manyfold (やえはたえ, Yae Hatae) (literally, eightfold and twentyfold), many clouds (やくも, Yakumo) (literally, eight clouds), millions and millions of Gods (やおよろずのかみ, Yaoyorozu no Kami) (literally, eight millions of Gods), etc. It is also guessed that the ancient Japanese gave importance to pairs, so some researchers guess twice as four (よ, yo), which is also guessed to be a holy number in those times because it indicates the world (north, south, east, and west) might be considered a very holy number.
• In numerology, 8 is the number of building, and in some theories, also the number of destruction.

• In the Middle Ages, 8 was the number of "unmoving" stars in the sky, and symbolized the perfection of incoming planetary energy.

• In association football, the number 8 has historically been the number of the Central Midfielder.
• In baseball:
  • The center fielder is designated as number 8 for scorekeeping purposes.
• In rugby league:
  • Most competitions (though not the Super League, which uses static squad numbering) use a position-based player numbering system in which one of the two starting props wears the number 8.
• In the
  CST
  .

• In
  octarine
  .

• An "eighth" is a common measurement of
  psilocybin mushrooms.^[27]
• In Colombia and Venezuela, "volverse un ocho" (meaning to tie oneself in a figure 8) refers to getting in trouble or contradicting oneself.
• In China, "8" is used in chat speak as a term for parting. This is due to the closeness in pronunciation of "8" (bā) and the English word "bye".

• A figure 8 is the common name of a geometric shape, often used in the context of sports, such as skating.^[28] Figure-eight turns of a rope or cable around a cleat, pin, or bitt are used to belay something.^[29]