Prime (symbol) facts for kids
Quick facts for kids′
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The prime symbol ( ′ ), double prime symbol ( ″ ), triple prime symbol ( ‴ ), quadruple prime symbol ( ⁗ ) etc., are used to designate units and for other purposes in mathematics, the sciences, linguistics and music.
Although similar in appearance, the prime symbol should not be confused with the apostrophe ( ’ or ' ), single quotation mark ( ' or ‘ or ’ ), acute accent ( ´ ), or grave accent ( ` ); the double prime symbol should not be confused with the double quotation mark ( “…” or "…" ), the ditto mark ( ” ), or the letter double apostrophe ( ˮ ). The prime symbol is very similar to the Hebrew geresh, but in modern fonts the geresh is designed to be aligned with the Hebrew letters and the prime symbol is not, so they should not be interchanged. All of these similar-appearing symbols have different meanings, and their character-codes are treated differently by typesetting and font rendering software.
Designation of units
The triple prime ( ‴ ) in watchmaking represents a ligne or 1/12 of an inch. It is also occasionally found in historical astronomical works to denote thirds (1⁄60 of a second of arc).
Likewise, a quadruple prime ( ⁗ ) denotes fourths (1⁄60 of a third, a convention already used by Jamshīd al-Kāshī).
- See also: Positional notation#Sexagesimal system
Prime (symbol) Facts for Kids. Kiddle Encyclopedia.