I've always known that the sound [s] in #Hebrew is written with two letters in different words: Samekh and Shin, the latter being also the letter for the Sh-sound. However, I was today years old when I learned actually why. Historically, many centuries ago, the letter Shin didn't represent S at all: it represented the Sh-sound and, believe it or not, the voiceless L (like Welsh LL, Zulu and Quenya Hl) — pronounce a long "l", and still while pronouncing it, remove the voice, the vocal cords vibration, and you'll get this sound.
Later on, the voiceless L merged with S completely, that's why we have now both Samekh and Shin for S in Hebrew.
#TIL #RandomLinguisticFact