Hosting
aka: hostaka: hosting platform
The Quick Version
Someone else's always-on computer that serves your website to the world.
How it actually works
A hosting platform takes your built files, stores them on servers distributed around the world, and responds to every visitor request. Modern platforms also run your build step automatically whenever you push.
Why does it matter?
Your laptop is not the internet. Hosting is what makes your site reachable at 3am while you sleep.
Example
Vercel, Netlify and Cloudflare Pages are hosting platforms.