Google has released a new episode of its Search Central Lightning Talks, which focuses on rendering strategies, an important topic for web developers.
In this video, Martin Splitt, a Developer Advocate at Google, explains the intricacies of different rendering methods and how these approaches impact website performance, user experience, and search engine optimization (SEO).
This episode also connects to recent discussions about the overuse of JavaScript and its effects on AI search crawlers, a topic previously addressed by Search Engine Journal.
Splitt’s insights offer practical guidance for developers who want to optimize their websites for modern search engines and users.
What Is Rendering?
Splitt begins by explaining what rendering means in the context of websites.
He explains rendering in simple terms, saying:
“Rendering in this context is the process of pulling data into a template. There are different strategies as to where and when this happens, so let’s take a look together.”
In the past, developers would directly edit and upload HTML files to servers.
However, modern websites often use templates to simplify the creation of pages with similar structures but varying content, such as product listings or blog posts.
Splitt categorizes rendering into three main strategies:
Pre-Rendering (Static Site Generation)
Server-Side Rendering (SSR)
Client-Side Rendering (CSR)
1. Pre-Rendering
Screenshot from: YouTube.com/GoogleSearchCentral, January 2025.
Pre-rendering, also known as static site generation, generates HTML files in advance and serves them to users.
Splitt highlights its simplicity and security:
“It’s also very robust and very secure, as there isn’t much interaction happening with the server, and you can lock it down quite tightly.”
However, he also notes its limitations:
“It also can’t respond to interactions from your visitors. So that limits what you can do on your website.”
Tools such as Jekyll, Hugo, and Gatsby automate this process by combining templates and content to create static files.
Advantages:
Simple setup with minimal server requirements
High security due to limited server interaction
Robust and reliable performance
Disadvantages:
Requires manual or automated regeneration whenever content changes
Limited interactivity, as pages cannot dynamically respond to user actions
2. Server-Side Rendering (SSR): Flexibility with Trade-Offs
Screenshot from: YouTube.com/GoogleSearchCentral, January 2025.
Server-side rendering dynamically generates web pages on the server each time a user visits a site.
This approach enables websites to deliver personalized content, such as user-specific dashboards and interactive features, like comment sections.
Splitt says:
“The program decides on things like the URL, visitor, cookies, and other things—what content to put into which template and return it to the user’s browser.”
Splitt also points out its flexibility:
“It can respond to things like a user’s login status or actions, like signing up for a newsletter or posting a comment.”
But he acknowledges its downsides: