Q . What is Wetland?
A . Wetland is literally a "wet area". All land with water moisture is called wetland. The water can be fresh water (normal water) or salt water like marine water. Wetlands include rivers, lakes, swamp, and their riparian zones covered with wet soil and mud, as well as tidal flats and forests which grow soaking in the marine water (e.g. Mangrove forests in the southern region). Wetlands are not only natural areas but also human-made areas such as paddy fields and dams if they have water.
In order to conserve wetlands, 35 categories of wetlands are defined in a treaty called the Ramsar Convention, which was made up among many countries. They include even frozen land in the arctic area called "tundra  and water holes dug by human beings to remove soil and gravel. It is amazing how many kinds of places the word "wetland" refers to.

All land with water
moisture is called wetland.

Types of Wetlands
Types of Wetlands