What is one basic difference between endodermis and epidermis

Epidermis is the outermost layer of closely arranged living cells without any intercellular spaces forming a boundary between the plant and the external environment. It protects the plant from water loss, regulates the exchange of gases, secretes metabolic compounds. It also helps in absorption of water and minerals from the soil in roots. 

Endodermis is the innermost layer of cells lying between the cortex and the vascular tissue. It has a strip of water proof material (suberin) known as the casparian strip that forces water through the endodermal cells and in such a way regulates the amount of water entering the xylem.