Server-Side Rendering
Learn what server side rendering is and why it’s preferable to client-side (browser) rendering. You’ll also learn how Gatsby uses server-side rendering to create static websites.
What is Server-Side rendering?
Server-side rendering means using a server to generate HTML from JavaScript modules in response to a URL request. That’s in contrast to client-side rendering, which uses the browser to create HTML using the DOM.
Server-side rendering with JavaScript works similarly to other server-side languages such as PHP or .NET, but with Node.js as the runtime environment. When the server receives a request, it parses the JavaScript modules and data required to generate a response, and returns a rendered HTML page to the browser.
Single-page applications use client-side rendering. All URL requests are redirected to the same bare-bones HTML document, like the example that follows.
Client-side rendering fills in the rest. Views for specific URLs are managed by a JavaScript routing mechanism. Each URL request triggers a DOM update instead of a network request. As a result, sites that use client-side rendering can feel “snappier” and more responsive to user actions. However, client-side rendering has two significant drawbacks.
- Site visitors have to wait for the JavaScript bundle to load and for the browser to build the DOM before any content is visible. They may see a blank page or loading image while JavaScript loads.
- Your bare bones HTML document lacks the keyword, description, and social media metadata (e.g. OpenGraph) necessary for search engine optimization and social media sharing.
Server-side rendering addresses both concerns by creating HTML at run time, when the server receives a browser request). Search engines can index your URLs. Visitors can share them on Facebook or Twitter.
Instead of purely server-side rendering, Gatsby uses the same APIs to create static HTML at build time when you use gatsby build. Gatsby-rendered HTML pages give you the SEO and social sharing advantages of server-side rendering with the speed and security of a static site generator.
Learn more
Why server-side render? from Behind the Scenes: What makes Gatsby Great
What is a Static Site Generator? from the Gatsby docs