Stainless Steel Camlock style disconnects are a great combination of cost and function. Pushing tubing onto hose barbs and adjusting worm clamps eventually gets tiring, camlocks make connecting and disconnecting a breeze between your vessels, chillers, pumps and hose sets.
The quick connection portion of the camlock system consists of male and female parts. The male is a cylinder with an external concave recess around the circumference and a front sealing face. Once inserted into the female coupling, a set of cammed arms are drawn back to apply pressure to the male's recess which locks the parts together and holds the male's sealing face tight to the captured gasket.
Ultimately, it is up to the user, but the most common connections are to use the male connect on the fixed brewery components while the female connect is installed on the more mobile parts like hoses. This is typically done so that the movable cam arms have room to swing.