The end of the year is always a good time to reflect on the small things in life, those things we normally take for granted but really make a difference. One of them, for any user of Japanese out there, is the small version of the kana letter tsu — っin hiragana,ッin katakana — and the many things we do with it on a regular basis.

So here’s to you, my little tsu.

One of the most intriguing things about this letter is its flexible pronunciation. A small tsu indicates what linguists call a geminate, or long consonant. That means, unlike most other letters in the kana syllabary, っ doesn’t have a single specific reading. Instead, its users’ manual reads something like this: shorten the preceding vowel slightly, then start with the sound of the subsequent consonant. The technical term for this in Japanese is 促音 (sokuon, geminate).