expand_less The most important Decko concept is the [[card]]. Cards are the basic building blocks of Decko websites, or decks.
Cards are inspired by wiki pages. Like wiki pages, cards have revision histories, human-friendly names, and easy in-place editing interfaces. But we don't call them pages, because the word page already has a pretty clear meaning on the web: a webpage. But on Decko, a given webpage might be constructed out of dozens or even hundreds of cards. Cards not only hold lots of different content that can be combined and recombined in flexible ways, they also determine how a webpage is structured, who can read it, and how it behaves.
In Decko, everything is a card: [[images]], [[users]], [[rules]], [[layouts]]... they're all cards. If you're thinking that you've heard this "everything is a X" story before, then you're right. Wordpress says that everything is a post. Drupal says that everything is a node. And so on. But Decko takes the idea further. When you break a Wordpress post into smaller bits, you get something that is not a post. Same for a Drupal node. But when you add more granularity to cards, you get more cards.