Final answer:
Neap tides occur when the Sun and Moon's gravitational forces are at right angles, resulting in lower high tides and higher low tides, and they happen twice a month during the quarter moon phases.
Step-by-step explanation:
Neap tides are a type of tide that occurs when the gravitational forces of the Moon and the Sun are perpendicular to one another with respect to Earth. This alignment results in lower-than-usual high tides and higher-than-usual low tides. Neap tides happen twice each lunar month during the first and third quarter moon phases when the Sun and Moon are at right angles to each other. Unlike spring tides, which occur when the Sun and Moon's gravitational forces align and reinforce each other to create higher high tides and lower low tides, neap tides result in a lesser variation between high and low tides.