The landing page is filled with a lot of airy concepts, but the 'how it works' section grounds it some:
Wilds: We, the people, are all citizens exploring this digital world, first as strangers. Strangers meet in the wilds. The wilds is the global feed. Meet a stranger here with content you like, add them as a contact. Think of your contacts list rather than follow a list as your digital address book.
City: A contact is someone you may see around, but you're not expecting to see their content when you're out scrolling or strolling in the city. In the city, a contact’s post is in the same feed as everyone else is on nextblock. To navigate around the city, you can use hashtags to visit different districts (single #) and intersections (two #s). When visiting a district or intersection, you see everything in the same order as everyone else visiting. It is a shared digital experience.
Neighborhood: When you find content from contacts you want to see more often, you can make them your neighbors. Your neighbors are people you've selected to be in your neighborhood. Every citizen on nextblock has a neighborhood where they can curate a digital space to control the access to their attention. You only see what they've posted, replied to, or zapped.
... and so on.