Someone talk me through socialing media algorithms work?

The short version: every platform shows a post to a small group first, watches what they do, and pushes it wider if they react well. What counts as reacting well differs. On instagram and tiktok watch time and shares matter a lot; on linkedin early comments do more; facebook leans towards stuff people talk about with friends. So instead of chasing each algorithm, ask: would someone stop scrolling for this, and would they send it to someone? Those two cover most of it. Which platform are you working on?