Data vs content: it's all about the context
When talking to people about Seams-CMS, I often tell people that Seams-CMS is not only a CMS but more of a Data Management System (DMS). And even though we don't call it Seams-DMS, we do primarily see and develop it as a DMS. So what is the difference between a CMS and DMS?
To explain, think about a set of numbers. For instance: 2, 7, 18, 42, 61. There is pretty much nothing we can do with these numbers, except acknowledging that they are, well, numbers. But these numbers might be the winning combination for a lottery OR these numbers are the combination of a vault. Or maybe these are the ages of family members. Or maybe even all of the previous explanations are true.
It all depends on the context in which your data is presented to the user. In some cases, the given data is entirely useless and are just mere "facts." But in a specific context, this data can become useful, priceless even. To understand data, we always need a context to represent this data. Then, and only then, data can make sense.
So if the difference between data and content is the context, what does this mean for a regular CMS? Most CMS systems will dictate the context for you: this is a page, here you can add X, Y, and Z. You can add tags. If you fill in this field, you define a slug for your page, and so on.
You must mold data in the shape of the given context, which kind of works when you mostly agree about this context. For this to work, such a CMS needs a "one size fits all" context. It must make sure that everybody can work within the given context of the CMS. But as it goes: One size fits all, mostly means, no size fits perfectly.
This is the reason why headless systems are so powerful: Instead of providing you with our context, you provide us with YOUR context that is tailored to your needs. You are not going to define pages when you don't need pages in your context. You can define whatever you want without worrying that data won't fit our context. It even allows you to change the context at a later point in time.
Because you specify your context through our content-types, you are entirely in charge of the context. All that Seams-CMS does is store and retrieve the data. Once you fetch the data from our system, you can place it into any context you want. So, for instance, a catalog of articles can be used for your e-commerce platform while at the same time, use it for generating real-life brochures or flyers.
This context-free behavior is why headless systems have won big time in the CMS world: it gives you complete control over the context of your data without interference of the management systems.