TL;DR;
Dynamic rendering is the process through which a crawlability issue of a website using Javascript is solved by serving robots a different, HTML static version of the web page.
What is dynamic rendering?
Dynamic rendering is a topic for advanced website developers and it is not a procedure we would recommend for beginners or for any website owners and entrepreneurs with technical skill levels below advanced. That being said, dynamic rendering is a process that was developed in order to solve potential crawlability issues for websites that use JavaScript. Most modern websites don’t just use static content. Javascript is included in the code used by most templates, plugins and extensions that any user would add to his website when using a webpage builder.
Unfortunately, Javascript can be hard to read and interpret by web crawlers. If you have connected your website to a Google Search Console account, you can check how crawlers see your web page by doing a URL inspection. It is not so uncommon to come across web pages that don’t display some of the content properly, due to Javascript. It all depends on the web building platform you are using and the way your template and plugins work. If that is the case, dynamic rendering can be used to create a static HTML version of the page to be served to the crawlers instead of the original version.