A Schottky diode conducts current in one direction only, just like a regular diode. Because of a different construction the forward voltage drop is low, only 0.2 volts, where a normal diode has 0.7 volts voltage drop in the forward direction. This makes it energy efficient. It also has a fast switching action.
Schottky diodes are used in power supplies and other applications where a low voltage drop is essential.
If,max: Maximum forward current (A)
VR,max: Maximum reverse voltage (V)