Webhooks let you tell TourCMS where to call out to third party systems or websites when something happens (a trigger event). When it calls a webhook TourCMS will include a pre-defined payload containing structured information about the event, in some cases it may wait for and process pre-defined response.
The pages linked below detail the various webhooks, their triggers, payloads and required responses.
Full Webhook list
Have TourCMS call a URL when something happens with regard to bookings (new booking, cancelled booking, payment made, expired quotation etc)
Have TourCMS call a URL when a check availability API request is made to the system, tell TourCMS whether to say yes or no