EDIT Eszett The eszett (ɛs\'tsɛt) is a lower-case letter used only in German to represent \"ss\" as in \"Straße\" (street). It is a ligature of the old German letter ſ (»long S«) and the letter z, hence the name eszett.

 edtrager  : : :  eki 

EDIT Common mistakes Sometimes in non-German writing the ß is used to replace the capital B because the writer doesn't know its meaning and likes the shape better than the one of the actual B.

In German, the ß is only used for lowercase writing and has to be replaced with ss in uppercase writing. See »WEIB« in the attached picure, where for once the capital B wrongfully takes the place of a nonexistent capital ß. There has also been the rule to replace it with "SZ", probably based on the misapprehension that the ß was based on "s" and "z". While having its use in the distinction between "MASSE" and "MASZE", it was probably only applied on ASCII-only equipment in the armed forces.

I have also seen the U+03B2 (Greek small letter beta) used in place of a ß.

 jsw  :  fxg 

EDIT History and Typographic Structure The letter is actually a ligature of the long "s" and the "round" "s" used in Renaissance scripts and broken (Fraktur) types. As the long s had no phonetic distinction and was just the s to be used within words, it went the way of many useless things and is no longer in use. The right part of the ligature already in use in fraktur scripts was misinterpreted as a 'z', which lead to the misnomer "Es-zett" and numerous historically incorrect shapes.

Based on: Jan Tschichold, "Meisterbuch der Schrift", Otto Mayer Verlag Ravensburg, 1965

 fxg  : : :  jsw 

EDIT Language With the latest orthographic reform, the ß is the letter to be used for the voiceless (or sharp) s after _long_ vowels (Müßiggang), while \"ss\" is to be used after _short_ ones (Genuss).

 fxg  :  213.47.148.180 

EDIT Synonyms
English: German B
German: Eszett, scharfes S

 de 

EDIT Ad: Jan Tschichold. In 1999, Max Bollwage showed conclusively that the ß is not a ligature of a long s and a round s, as Tschichold had believed. Actually, the round s as shown by Tschichold, does not appear like this in older scripts. Rather, the hook on the right half has always been a separate character, and its form has had its own history. Hans Peter Willberg concluded that the correct form of the ß is the so-called “Dreierles-s” where the right half looks similar to a three.

(Hans Peter Willberg: Typolemik. Verlag Hermann Schmidt: Mainz 2000.)

 213.47.148.180