A website that only relies on client-side languages is called a static website. This means that the webpages remain the same unless you edit the HTML code. To start with (back in the 90s), the World Wide Web was only made of static websites.
Progressively, the internet evolved to more dynamic websites. We call this web2.0.
Websites such as amazon, eBay, Facebook, etc. are dynamic websites. Their content changes constantly based on the user interactions with the site.
The following diagram summarises some of the key concepts of client-server web-based applications: