In a conventional Magento theme, all of the pages are generated on the server. This means that the client needs to fetch the entire page every time the user clicks on a link, and even with caching enabled, the pages need to be fully re-generated whenever part of the relevant data is modified. Not only does this make Magento resource-hungry, but it results in slow load time.
Instead of rendering the pages on the server and fetching them every time, ScandiPWA only fetches the data from the server (using GraphQL), and performs the rendering on the client-side, using React. The page is never actually reloaded - once the app’s JavaScript code has been loaded, the front-end magic happens without any help from a server. This is called a Single-Page Application, and it provides several advantages.
Now that the rendering happens on the client, the server does not need to render the entire page every time. It merely needs to serve the data required by the client, which can happen much faster.
Since the client is responsible for rendering the page, it knows the structure of the page even before requesting the data. As a result, we can implement a smooth transition to the next page, and display placeholder loaders until the data arrives.
Learn more about ScandiPWA: