Various languages have Diacritical marks, like ~ to make ñ, or ` to make è. Some languages allow you to combine more than one diacritical mark. Unicode supports that, letting you combine multiple marks from a pretty healthy list of marks. A lot of them come from the International Phonetic Alphabet, used by linguists to mark with excruciating detail exactly what was going on in the mouth of a speaker. And your browser turns that Unicode into just what you see on the screen: a letter with a very large number of decorations above and below it. Zalgo text (zalgo text discord) generators combine lots and lots of marks to make some pretty silly-looking text. Which, when used more and more in a block of text, does a great job of representing the increasing frustration of, say, a programmer who has been asked for the thousandth time why you can’t make a regular expression that matches nested HTML tags.

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How does zalgo text like this work?