The coastal type and topography of the coastal zone are material responses to the interaction between land and sea. According to their causes, coasts can be divided into three types: erosive coasts, accumulative coasts, and balanced coasts. According to land landforms, coasts can be divided into plain coasts, mountainous hilly coasts, and biotic coasts.

From a geological perspective, the shallow sea area at the edge of the ocean is a continent submerged by seawater, known as the continental margin. The continental margin accounts for 15.3% of the total ocean area, with the main body being the continental shelf, followed by the continental slope and continental base. Passive continental margin, also known as Atlantic type continental margin. The so-called stable continental margin refers to a continental margin that has been in a relatively stable state for a long time in terms of structure. Its crust is a transition zone from oceanic crust to continental crust, with continents and oceans located within the same rigid lithospheric plate. It does not have a trench subduction zone, and its early splitting stage is located within the plate, followed by passive movement with the splitting plate, so there are no strong earthquakes.

Earth (English name: Earth; Latin: Terra) is the third planet from the sun and the only celestial body known to harbor and support life. About 29.2 percent of the Earth's surface is land, consisting of continents and islands. The remaining 70.8 per cent is covered by water, mostly by oceans, bays and other brackish bodies of water, but also by lakes, glaciers, rivers and other freshwater bodies, most notably glaciers, which together form the hydrosphere.