Serverless as a term has become separated from any particular technology, although serverless functions are what many people think of when they say serverless.
Build and run applications without thinking about servers
JAMStack, similarly, is contrasted against manually managing servers.
When we talk about “The Stack”, we no longer talk about operating systems, specific web servers, backend programming languages, or databases.
The Jamstack is not about specific technologies. It’s a new way of building websites and apps that delivers better performance, higher security, lower cost of scaling, and a better developer experience.
Fast and secure sites and apps delivered by pre-rendering files and serving them directly from a CDN, removing the requirement to manage or run web servers.
In both cases, we're not thinking about physical infrastructure anymore.
You're not running your own CDN, your own servers, your own databases, or your own
Both are on the side of buy vs build.