Acronyms are abbreviations formed by the initial letters taken from a word or series of word that is itself pronounced as a word. E.g RAM, NOUN, HTML etc
"What is the acronym for Uninterrupted Power Supply?"
Apostrophes in orthography means the text character (') that serves as a punctuation mark in various languages and as a diacritical mark in rare contexts. Also, it could mean a sudden exclamatory piece of dialogue addressed to someone or something absent.
"The main actor presented an apostrophe towards the end of the play about his struggles."