[Someone]

Twitter started as “an individual using an SMS service to communicate with a small group”, and SMS messages are 140 bytes (that may store 160 characters when using a 7-bit encoding such as https://en.wikipedia.org/wiki/GSM_03.38, but they didn’t go there)

I guess bumping the limit up while keeping the ability to interact with all kinds of SMS systems and ancient phones was a challenge, or just required waiting a few years for some of the weirder systems to die out.

[opencl]

The 140 byte limit actually didn't last very long, it was 140 Unicode code points since at least a decade ago. You could use 140 CJK (Chinese/Japanese/Korean) characters or 140 emojis, and if it didn't fit in an SMS they just sent a link to the tweet.

Interestingly when they doubled the character limit they also started double counting CJK characters so the limit is still effectively 140 for those languages.

[lifthrasiir]

> Interestingly when they doubled the character limit they also started double counting CJK characters so the limit is still effectively 140 for those languages.

CJK languages do tend to be relatively dense when written and counted by their code points.