Some useful terminologies related to rendering on the web

 Rendering

• SSR: Server-Side Rendering - rendering a client-side or universal app to HTML on the server.
• CSR: Client-Side Rendering - rendering an app in a browser, generally using the DOM.
• Rehydration: “booting up” JavaScript views on the client such that they reuse the server-rendered HTML’s DOM tree and data.
• Prerendering: running a client-side application at build time to capture its initial state as static HTML.

Performance

• TTFB: Time to First Byte - seen as the time between clicking a link and the first bit of content coming in.
• FP: First Paint - the first time any pixel gets becomes visible to the user.
• FCP: First Contentful Paint - the time when requested content (article body, etc) becomes visible.
• TTI: Time To Interactive - the time at which a page becomes interactive (events wired up, etc).

Reference: developers.google.com