Silent letters in English aren't random, most of them used to be pronounced

Always assumed English just threw silent letters in to torture learners, but the actual history is more interesting.

The "k" in "knight" wasn't always silent. Earlier people really did pronounce it — k-nicht, closer to how German still says related words like "Knie" for knee with the k intact. The sound quietly dropped over time but the spelling froze in place, so we're stuck writing a letter nobody says.

Then there's the flip side: some silent letters were added on purpose, after the fact, to make a word look like it belonged to a certain trend or root. The "e" in "house" is that kind of thing — decoration more than pronunciation. And the classic "silent e" at the end of a word often exists to reach back and change the vowel: it's the reason "hop" becomes "hope."

Someone shared a mnemonic they'd kept for 40 years: vowels are being hunted by naughty letters, and the silent e stands guard at the end of the word to protect the vowel. Cheesy, but it stuck with them since childhood, which is kind of the point of a good mnemonic.

I am interested in this & want to know moreof such whose backstory behind silent words.