Number sign

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Number sign is a name for the symbol #, which is used for a variety of purposes including, in some countries, the designation of a number (for example, "#1" stands for "number one"). "Number sign" is the preferred Unicode name for the code point. Its Unicode code point is U+0023, and its ASCII value is 35 (0x23 in hexadecimal). The html entity is # or #.

In the United States, the symbol is usually called the pound sign, and the key bearing this symbol on touch-tone phones is called the pound key. In Canada, this key is most frequently called the number sign key. In most English-speaking countries outside North America, the symbol is usually called the hash, and the corresponding telephone key is the hash key. Beginning in the 1960s, telephone engineers have attempted to coin a special name for this symbol, with variant spellings including octothorp, octothorpe, octathorp, and octatherp.[1] None has become universal or widely accepted. In non-English speaking nations, other names for this symbol are also used.

In many parts of the world, including parts of Europe, Canada, Australia, and Russia, number sign (or equivalents in local languages) refers instead to the "numero" sign (Unicode code point U+2116), which is often written simply as No.

The symbol is easily confused with the musical symbol called sharp (). In both symbols, there are two pairs of parallel lines. The key difference is that the number sign has compulsory true-horizontal strokes while the sharp sign does not have them. Instead, the sharp sign has two slanted parallel lines which rise from left-to-right. Both signs may have true vertical lines; however, they are compulsory in the sharp, but optional in the number sign (#) depending on typeface or handwriting style. Thus only the number sign may have an italic appearance.


Usage and naming conventions in North America

Mainstream use in the US as follows: when it precedes a number, it is read as "number", as in "a #2 pencil" (spoken aloud as: "a number two pencil"); however, when it follows a number it is read as "pounds" referring to the unit of weight, as in "5# of sugar" (spoken aloud as "five pounds of sugar"). The first form is more widely used by the general population while the second form is more specifically used in the food service and grocery/produce industries, or other fields where units of pounds (as weight) need to be hand-written frequently or repetitively. Most others use the abbreviation "lb." or "lbs."

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