Two pairs of crossing strokes, used as a number mark, a hash and a musical sharp.
Also known as: Hash, Hashtag, Pound key, Octothorpe
The number sign marks a numeral in North American usage, tags a topic as a hashtag, and is called the hash or pound key on telephones. It is a distinct character from the musical sharp, which it closely resembles.
Marks a following numeral, as in #1, principally in North American usage.
Chiefly North America · Contexts: Software
Tags a word or phrase as a searchable topic on social platforms, a use that spread from chat channels.
Contexts: Software
Is called the pound key on North American telephone keypads — a different sense from the pound currency sign, which is a distinct character.
The telephone 'pound key' and the currency pound sign £ are unrelated characters that share a spoken name.
Contexts: Software
Is frequently mistaken for the musical sharp sign, which has slanted horizontal strokes and upright vertical ones — the opposite of this character.
Contexts: Software
Two horizontal strokes crossed by two vertical strokes, forming a grid of four cells.
Both are called 'pound' in different contexts; they are unrelated characters.
The same character. Most scripting languages use it to mark the rest of a line as a comment.
Different characters that render alike. The musical sharp slants its horizontals and keeps its verticals upright; this sign does the reverse.