Plains are FLAT areas with NO mountains.
The Coastal Plains
They both have plains
one is hilly and the other is flat
Coastal plains and interior plains are both structurally flat. They also play major roles in the carbon and nitrogen cycle.
The major distinguishing features of the northern plains and coastal plains are that the northern plains have varied elevation and low relief, while the coastal plains have low elevation and low relief. The coastal plains lie along the shore, but the northern plains are surrounded by land surface.
One major difference between Coastal plains and Interior plains is in elevation. Coastal plains have low elevation and low relief. Interior plains have varied elevation and low relief. Coastal plains also lie along the shore while Interior plains are surrounded by other land.
Another name for coastal plains are lowlands or littoral plains. These are flat, low-lying areas adjacent to coastlines that are formed by the deposition of sediment carried by rivers or the sea. Coastal plains are often fertile and support diverse ecosystems.
it mostly has rocky land
the great plains is bigger than the coastal plains.
Terra firma
The Deccan Plateau is very dry unlike the coastal plains are rich in agriculture.