In this TikTok and reel world, user attention is ever-decreasing, making the loading speed paramount. Users crave speed, responsiveness, and smooth interactions. To meet this demand, developers employ techniques to enhance perceived performance. Skeleton screens, fun facts on load, and dynamic icons (like a moving car on a cab app's map) all grab and hold user attention.

Next.js, a robust React framework, utilizes Server-Side Rendering (SSR) and client-side hydration to optimize how users perceive load times—exemplifying one such effective technique.

Understanding the Perceived Speed

When you visit a website and the content appears immediately, it gives the impression of a fast-loading page, even if the data fetching time remains constant (compared to web apps built using other languages and frameworks). Next.js uses this phenomenon by providing pre-rendered HTML content for the initial view, which swiftly gives users a sense of responsiveness. This means that users can see the content on their screen without delay, making the experience more seamless and enjoyable.

The Next.js Approach

Next.js, built on React, combines the best of server-side rendering and client-side interactivity. Here's how it achieves the illusion of speed:

Server-Side Rendering (SSR):

Next.js employs SSR to pre-render the page on the server based on the requested URL. This pre-rendered HTML content is sent as the initial response to the user's request on the browser.

Client-Side Hydration:

Simultaneously, Next.js transmits the required JavaScript bundle for the page. As this JavaScript loads and runs on the client side, React takes over and "hydrates" the initial HTML. This process adds interactivity, transforming the static content into a fully functional and interactive React application.

By separating the rendering of the initial content on the server and the application logic on the client side, Next.js balances perceived speed and interactivity.

The Illusion at Play

The trick here is all about how users perceive it. The first HTML content pops up fast, giving the illusion of a lightning-fast page load. The subsequent hydration process amplifies this impression, making the page interactive and fully functional. Users are captivated right from the start, staying immersed in the experience.

Benefits Beyond Perception

While this perceived speed greatly enhances user satisfaction, it also has tangible benefits. Search engines can efficiently crawl and index the pre-rendered content, improving the application's search engine optimization (SEO). Additionally, users on slower devices or connections perceive a faster experience due to the swift display of the initial content.

Conclusion

Next.js optimizes user experience by swiftly displaying an initial application view, giving a sense of speed. Using SSR with client-side hydration, Next.js efficiently prioritizes content delivery and interactivity. Striking the right balance keeps users engaged and satisfied. In today's fast-paced digital era, it's all about creating experiences that perform well and feel lightning-fast for the end-users.