Online booking glossary: the terms you need to know

Deposit, advance payment, iCal, OTA, channel manager, RevPAR, 3-D Secure… The key terms of vacation rental and appointment booking, each defined in one or two sentences.

This glossary defines, in one or two sentences each, the terms you will come across when you open online bookings, whether for overnight stays or for appointments. It was written by the team behind GDA Kraft Booking, the WordPress booking plugin published by Global Digital Agency, but the definitions apply whatever tool you use. When a term has its own detailed article, a link points to it.

Payment terms

Deposit (French “acompte”): an amount paid in advance that firmly commits both parties; the customer still owes the balance. See Deposit or “arrhes”: what is the difference?.
Arrhes (French law): an amount paid in advance that leaves each party free to withdraw, the customer by forfeiting the amount, the business by refunding twice the amount.
Balance: the amount still due after the deposit, usually paid before arrival or on the day of the appointment.
Off-session payment: a charge on a saved card made without the customer being present on the site, for example the automatic collection of the balance.
Strong customer authentication (SCA): a European requirement to verify the payer's identity using at least two of the following: something they know, something they have and something they are.
3-D Secure: the protocol banks use to apply strong authentication to online card payments. See Strong authentication and 3-D Secure.
Hosted payment page: a page served directly by the payment provider (Stripe, in this case), on which the customer enters their card without your site ever seeing the data.
Service fee: in GDA Kraft Booking, an amount added to each online payment and shown to the payer: 0.9%, reduced to 0.45% until 30 June 2027.
Credit note: an accounting document issued when you refund, cancelling all or part of an invoice.
Offline payment: a payment received by bank transfer, cheque or cash and recorded manually in the tool.
Free core and Connect add-on: in GDA Kraft Booking, the edition currently downloaded from the Kraft GDA client area (free account) includes everything: online payment, appointments, Kraft Console, multilingual support, with no add-on. The free core with no account is the WordPress.org edition, available for free on WordPress.org; it has no online payment, appointment mode or Kraft Console, which belong to the separate GDA Kraft Booking Connect add-on, available from Downloads in the client area (or install the complete edition instead, never both).

Distribution terms

Direct booking: a booking taken on your own website, with no commission-based intermediary.
OTA (Online Travel Agency): an online booking platform such as Airbnb, Booking.com or Vrbo. See What is an OTA?.
Rate parity: a clause that required a host not to offer a lower price on their own site than the one shown on a platform.
iCal: a standard calendar format (.ics files) used to exchange booked periods between two tools. See What is iCal?.
iCal feed: a web address that publishes a calendar in iCal format and that other tools re-read at regular intervals.
External block: a period imported from a platform through iCal, with no details about the guest.
Channel manager: software that connects a property to several platforms through an API to synchronise availability, prices and bookings. See What is a channel manager?.
PMS (Property Management System): property management software that centralises bookings, planning, invoicing and often distribution.
Double booking (or overbooking): two bookings accepted for the same dates on the same unit.

Rate and calendar terms

Base rate: the nightly price applied when no season covers the date.
Season: a period with its own nightly price and its own length-of-stay rules.
Minimum stay: the number of nights below which a booking is refused.
Orphan night: an isolated night between two bookings, too short to be sold under the minimum stay in force.
Buffer days: days blocked automatically before or after a stay for cleaning or preparation.
Weekly price: a flat amount for 7 consecutive nights that replaces the sum of the nights.
Length-of-stay discount: a percentage discount granted from a certain number of nights.
Extra: a service added to the stay (cleaning, linen, breakfast), charged per stay, per night or per person.
Tourist tax: a local tax due per person and per night, collected by the host on behalf of the local authority. The French “taxe de séjour” applies in France only; rules elsewhere depend on the country and the municipality.

Performance indicators

Occupancy rate: nights sold divided by nights available over a period.
ADR (Average Daily Rate, the average price per night sold): accommodation revenue divided by the number of nights sold.
RevPAR (Revenue Per Available Room): accommodation revenue divided by the number of nights available. All three indicators are explained with an example in Occupancy rate, ADR and RevPAR.

Appointment terms

Service: what the client books, with a duration and a price.
Staff member: the person or resource who delivers the service and holds the schedule.
Slot: a time offered to the client, calculated from the service duration and the schedule.
Buffer: a gap added before or after an appointment.
Group session: a service on a fixed date that welcomes several participants, up to a set capacity.
Waiting list: clients signing up for a full session, who are notified when a place becomes free.
No-show: a client who does not turn up and did not cancel.

How to use this glossary

Legal terms (deposit, arrhes, tourist tax) have legal consequences: their definitions here are simplified and do not replace reading the texts or the advice of a legal professional or an accountant. Several of them, such as arrhes and the taxe de séjour, are French concepts and apply in France only. Technical terms (iCal, channel manager, 3-D Secure) are explained to help you choose your tools and understand their limits.

Frequently asked questions

What is the difference between a deposit and arrhes?

A deposit (French “acompte”) commits both parties, whereas arrhes allow each party to withdraw, either by forfeiting them or by refunding twice the amount. This distinction comes from French law and applies in France only: in a contract between a business and a consumer, amounts paid in advance are treated as arrhes unless otherwise stated.

Does an iCal feed synchronise prices?

No. An iCal feed only carries booked or blocked periods, never prices, amounts or guest contact details.

Is RevPAR more useful than the occupancy rate?

It is complementary: the occupancy rate measures how full you are, ADR measures the price achieved, and RevPAR combines the two into a single figure of revenue per available night.

Is GDA Kraft Booking a channel manager?

No. GDA Kraft Booking synchronises availability with Airbnb, Booking.com and Vrbo through iCal, with no API connection and no price synchronisation.