In Dungeons & Dragons, the Sending spell can convey exactly 25 words. In reality, linguists are unable to precisely pin down what a word is. Sending is one of only a few long-distance magical communication methods in the worlds of D&D, and this makes it an important tool in the hands of those who run large organizations, kingdoms, or empires.

This implies that mystical linguists in D&D worlds are out there pushing the technological boundaries of what constitutes a "word", experimenting with different hyphenation techniques, and assembling new compound languages like the fabled "Hypergerman", which are particularly amenable to compounding. All to improve the efficiency of
Sending, and eke out a little more information from each scarce spell slot. How much additional information can you add if you start experimenting with tones?

I'm just imagining the æther-messengers of the Imperial Bureaucratic Service constructing Sendings with all the comprehensibility of a dialup modem sound, and blasting out whole paragraphs of information to someone on the other end who has
Keen Mind and has to spend an hour with a diabolical grammar and particle reference translating this data-pulse back into the trade tongue.
@tilde
All of these genetically lucky magi waste their lives on Sending instead of studying radio waves (and laypeople have no incentive to do so). That's why DnD technology plateaus for millennia. Magic keeps everyone in relative stasis and ultimately prevents advancement.
@jcutting @tilde "radio waves work the same way they do in real life in a secondary world where magic exists" is a pretty big assumption though