The tidal force is the force of gravity between the Earth and the Moon that creates the ocean tides on Earth. Gravity causes the planet and the oceans to buldge on the side closest to the Moon and also the side farthest from the Moon. This creates two high tides and two low tides during each solar day at any coastal location on Earth. Other planets also have tidal forces with their moons. The tidal forces can cause the moon to bend and warp, causing heat from friction on the interior of the moon.
Spring tides are the largest tides.
They happen at the standard high tide times at which the Moon is in the Full or New phase. The Sun, Moon, and Earth are roughly aligned, increasing the intensity of the tides. Neap tides occur when the Moon is in 1st or 3rd quarter phases. These are the weakest tides, since the Moon is perpendicular to the line between the Sun and the Earth. Pg 143-144 Advanced Question 27 .