A channel manager sits between a property's inventory and the many places it sells — Booking.com, Expedia, Airbnb, the direct site — pushing rate and availability updates to all of them and pulling reservations back, so a room sold on one channel is instantly closed on the others. It's what makes selling across several OTAs at once manageable without double-booking.
Channel managers are part of the wider distribution stack alongside a booking engine and often a property management system. They solve a multi-channel sync problem; they don't, by themselves, reduce the commission those channels charge.
Why it matters for direct booking
Channel management is a distribution-breadth tool — it spreads inventory across OTAs but does not, by itself, reduce their commission. A direct booking channel is the complement: it captures the bookings a property would rather not pay commission on, beside whatever distribution it runs.