A plumbed coffee machine (like this) connects directly to your home's water line. So instead of drawing water from an onboard water tank, it draws water straight from your plumbing. This can be very convenient because it avoids the need to refill the water reservoir, but it does make it difficult to move your coffee maker if you reorganize your kitchen. It’s also common for a plumbed coffee machine to include drainage from the drip tray so that it never needs to be emptied.