In parts of the world where the sea has tides, the tide comes in and out twice a day, so there are two high tides (tide fully in, that is covering most of the shoreline) and two low tides (tide out, that is, the shoreline or beach is exposed). Even though you can have high tide and low tide, the tide does not come in or go out to the same distance all the time. Sometimes, the high tide, is VERY high, that is, it has come in further than usual. The low tide will also go out further than usual at that time. This is called a spring tide. The neap tide is when high tide doesn't come in as far as usual and the low tide doesn't go out as far either. Whether you have neap tides or spring tides depends on the relationship of the moon and the sun to the earth. When both moon and sun are on the same side of the earth, they are both pulling in the same direction, so you get higher tides (spring tides). This also happens when the sun and moon are on directly opposite sides of the earth. When the sun and moon form a right angle with the earth, their pulls tend to cancel each other out a bit, so you get lower (neap) tides.