What are spring tides and neap …

Spring Tides
Spring tides are the result of the moon and sun working together to exert more pull on the earth's oceans. When the moon is in its full and new stages the earth, sun and moon are all aligned. This extra gravity pulling on the same point of the earth causes stronger high and low tides. These tides are named spring tides not because of the season but because the tides are springing stronger up and down.

Neap Tides
Neap tides are the result of the moon and sun working against each other's pull. When the moon is in its first and third quarter phases the earth, sun and moon are at a right angle to each other. Though the moon's pull is stronger, the sun's gravitational pull is lessening the effect of the moon's gravitational pull on the oceans. This means that twice a month we experience smaller high and low tides than normal.