A channel manager can be seen as a gateway that can transfer information to different systems. When you have a reservation system (PMS) and adjust price or availability information in it, the channel manager will pass this on to the booking channels. Without a PMS, you can make these changes directly in the channel manager. The other way around, the reservations from the booking channels automatically appear in the channel manager. If you have a PMS, they will also automatically appear in your booking overview. This way, your information is always up to date.