Ƒ

The letter F with hook (majuscule Ƒ, minuscule: ƒ) is a letter of the Latin alphabet, based on the italic form of f; or on its regular form with a descender hook added. A very similar-looking letter, ⟨ʄ⟩ (a dotless j with a hook and a horizontal stroke), is used in the IPA for a voiced palatal implosive.

Ƒ is used in writing the Ewe language in a straight form to represent the sound [ɸ], as distinct from the letter F, which represents an [f].

The minuscule italic ƒ, also called the florin sign, is used as a symbol for several currencies, including the former Dutch guilder, the Aruban florin, and the Netherlands Antillean guilder. It can be found as italic in non-italic fonts.

The italic ƒ has been used to denote mathematical functions, or to indicate aperture in photography (e.g. ƒ/2.8) in place of the more common italic f (in serif fonts) or oblique f (in sans-serif fonts).

Older fonts and character encodings included only the minuscule form for its use as an abbreviation. Unicode includes both the majuscule and the minuscule. Because of its origin, the italic ƒ (f with a hook) looks exactly like the italic f (f) in some typefaces. Ƒ and ƒ occupy code points U+0191 Ƒ LATIN CAPITAL LETTER F WITH HOOK and U+0192 ƒ LATIN SMALL LETTER F WITH HOOK in Unicode respectively, and may be entered by appropriate input methods.

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