Classic monolithic architecture
We have an editing interface (legs) where you can author your content and then of course you have the database which you think of as the body in this metaphor and then you have an integrated head. So this is the thing that makes the web pages visitors will see. So this is the classic system where everything is integrated as one monolithic system.
The point of the headless system is not actually that you do not want heads. It is that you can pick and choose. So you still have your authoring interface. You have your data backend where you have all your documents and do all your backend programming. But then the head! You severed the integrated head. You do not want it. Because you want to pick and choose your heads.
So maybe you like Ruby. So you have your website as a ruby head. And then maybe someone asks to have your content on some screen at some airport somewhere. And maybe you have an Alexa skill that takes some of your content and presents it to a voice interface so you build all these kinds of heads. Or maybe you have a podcast XML generator that is one of your small heads.
So you can just pick and choose and your content can go into the future. And it can be suited to all kinds of technologies that are upcoming without actually re-authoring your content in any way, as long as you model your content properly.
So that is the grand idea of the headless architecture. Not that you do not have a head but you have several heads that you can change them out as needed.
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