Hi, Easy Talk, you requested some information on lunar tides?
Lunar tides are caused by the moon's gravitational pull on the earth. There is not much the moon can pull on from the earth, because it is able to hold most things to itself. Water is constantly moving, so the earth fails to hold that back. The moon grabs anything it can get, and since the earth pulls everything but water, the moon pulls as much of that as possible towards itself.
There are two high tides, and two low tides each day, with about 12 hours between each.
Wind and currents make waves, and the gravitational motion of the moon pulls a bulge of ocean out towards itself, making a high tide. On the side of the earth facing away from the moon, it is also pulling the water in a bulge, but this time away from other waters. This causes a low tide.
Since the earth rotates, two tides occur a day, on each side.
I will post a link to my source, that also includes information on the sun and moon's combined efforts on tides, as response to the original poster.