How does a kitchen display system work?
A kitchen display system — KDS — is a screen in the kitchen showing the orders that need making, in the order they need making, which staff mark as they move. It replaces the printed ticket: instead of paper arriving and being spiked, the order appears on a screen and is updated as it is cooked.
The states a ticket moves through
Most kitchen displays work on a small set of states. An order arrives and waits to be accepted. Somebody accepts it, which tells the rest of the system the kitchen has seen it. It is started when cooking begins, marked ready when it can leave the pass, and completed when it has.
A recall exists for the case that matters in a real kitchen: something marked ready by mistake, or sent back. Without it, staff work around the system rather than in it.
Why the states are the point
The states are not bookkeeping. They are what lets the front of house tell a customer where their order is without walking into the kitchen, and what lets the system know when to decrement stock — food is used when it starts being cooked, not when somebody clicks add to cart.
They are also the only honest source of preparation times. A report on how long food takes is only meaningful if it is measured from something the kitchen actually did.
One queue, or one per channel
A kitchen that takes counter orders, web orders, delivery-platform orders and table orders can end up with a tablet per channel — the situation many restaurants know as tablet hell. Each screen has its own alert and its own order of arrival, and somebody has to merge them mentally.
A kitchen display that receives every channel puts them in one queue in the order they arrived. This is usually the largest practical improvement a KDS makes, and it depends entirely on whether the ordering channels feed the same system.
What a kitchen screen should not show
A screen on a kitchen wall is visible to everyone who passes it, including delivery drivers and sometimes customers. It does not need the customer’s name, phone number, address, or what they paid — the kitchen needs to know what to cook.
Leaving that information off is a privacy decision made once, in the right place, rather than a policy about who is allowed to stand where.