Question

what is meant by spits and bars

Answer 1

A spit or sandspit is a deposition bar or beach landform off coasts or lake shores. It develops in places where re-entrance occurs, such as at a cove's headlands, by the process of longshore drift by longshore currents.
A bar is very similar to a spit. It is a ridge of sand or shingle which forms across the mouth of a river, the entrance to a bay or harbour. It is usually parallel to the coast. Bay. A wide indentation into the land by the sea, protected on each side by a headland.