The terms "pop-up waste" and "click-clack" are commonly used to describe the two different kinds of drain plugs found at the bottom of a sink basin or tub. In general, the purpose of drain plugs is to handle clogs or blockages that would otherwise compromise the efficiency of your drainage system. The difference between "pop-up" and "click-clack" waste is simply the way in which the drainage plug is opened and closed. The "pop-up" waste operates the drainage plug by lifting a lever, which is located directly behind the faucet, up and down. The "click-clack" waste doesn't involve any kind of lever system and is simply the drainage plug itself, which is operated by pushing it down (sometimes simultaneously turning it) in order to open and close the drainage plug. When the drainage plug pops up a "clack" is often heard and when pushed back down it makes a "click" sound, hence the origin of its name.

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