Server Side Rendering
You extracted the HTML file/String from your Javascript /React code on the server and then sent a plain and simple html file/string to the client/browser that it’ll immediately show to the user without any extra step Called Server Side Rendering. Top companies like Marvel, Netflix, Uber, Deliveroo, Nike, Hulu is using Next JS Server Side Rendering technology with front-end technologies like React JS. Server-side rendering is nice because: -Your content is visible to search engines like Google. The page loads faster than Client Side Rendering. server-side rendering is able to display a fully populated page on the first load for any route of the website. It maintains the idea that pages are documents, and if you ask a server for a document by URL, you get back the text of the document rather than a program that generates that text using a complicated API.
Client Side Rendering
You didn’t extracted the html string from javascript code on the server and sent the javascript file to the client/browser. Now, Browser can not show anything to the user immediately, Because now it’s the browser’s job to execute the javascript code, get the html string and then show it to the browser. This step can take fairly long time if your javascript file is big and you have a lot of components. In Client-side rendering when a user requests a different route it takes a long time in loading.