Oscillating Body this particular device acquires power from waves ascending and descending storing the energy inside the machine. It can vary in location as it can lay on the surface or be immersed by water in the middle of the sea/ocean.
Oscillating Water Column:Air Comes into a chamber through a tube and gets compressed and decompressed by the force of the waves and the turbine quickly collects the air as it's decompressed.Generating electricity.
Over Topping Device: What does this machine do this generator gathers water into its “basin” or Dam like design then when the water inside the device is higher than the sea (etc.) it will dispense its contents into where it originally came from when doing this it is thrust into a tube this turns the turbine (which I assume is inside the tube websites do not indicate where it is situates) then converts the energy produced when the turbine was revolved into electricity.
Tidal Power Generators
Tidal Barrages: Tidal Barrages are similar to the over topping device but there are a few key differences. When the tide of the water is high it collects the water inside the barrage then when the tide diminishes the barrage goes down letting the water go down, when leaving the barrage the water goes down with the force and with that it makes the turbines fans revolve around and produce electricity.
Tidal Fences: These are quite small nifty devices each fence contains a turbine (a fan like device) the fences are linked together like a fence as the name suggests when the water comes through it puts pressure on the turbine blades this makes the blades move and with that power it generates electricity.
Tidal Turbines: The same concept with tidal fences these are strategically placed where there is lots of tide so the water would come through and generate power. This machine built into the bottom sea level.