# Bookings A booking is a receipt. It records that somebody took a seat on a calendar, for a range of time. ## Bookable, calendar, seat - A **bookable** is what a site takes bookings for. - A **calendar** is a line of time with a capacity and an IANA time zone. - A **seat** is which of that capacity a booking took, from 0 upward. One database constraint holds every capacity, because a booking records its seat. A class of six needs no second mechanism. ## Holds A booking that waits for money is a hold, and a hold is an expiry rather than a status. There is no `expired` value. A held booking past its expiry **is** expired, and every reader works that out rather than wait for a writer. The next write to that calendar sweeps the dead holds. An hourly job is only tidy-up. ## The visitor's door A visitor books from the site's own page, at `POST /b/{public_id}`. That door is on the API surface, because the checks live there: the Turnstile check, the CORS grant and the rule about the client's address. Three reads sit beside it, and each is unauthenticated: the bookable, its days, and its free slots. Clave keeps a hash of the visitor's address and not the address. ## A calendar is archived, never deleted The row a calendar holds is a receipt of what somebody booked. A booking that points at nothing would stop holding its seat. ## Where mail goes `notify_to` on a bookable takes the same rule a form takes: an address on the account. Read [Forms](/concepts/forms). A message the visitor asked for by booking is outside that rule. A visitor is not a Clave user and never can be. Read [Bookings](/api/bookings). --- ## Where this page sits This is one page of the Clave documentation. Read it as a web page at https://docs.heyclave.party/concepts/bookings. Every page has a `.md` address, and https://docs.heyclave.party/llms.txt lists them all. - Previous: [Forms](https://docs.heyclave.party/concepts/forms.md) - Next: [Payments](https://docs.heyclave.party/concepts/payments.md) - Index: [Overview](https://docs.heyclave.party/index.md)