The revert statement is very similar to the require function. However, it does not evaluate any statement and does not depend on any state or statements. Hitting a revert statement means an exception is thrown, along with the return of unused gas, and reverts to its original state.
In the following example, an exception is thrown when the incoming value is checked using the if condition; if the if condition evaluation results in false, it executes the revert function. This results in an exception and execution stops, as shown in the following screenshot:
