Indexers permit instances of a class or struct to be indexed in the same way as arrays.
ÃÂ· Indexers are similar to properties except that their accessors take parameters.
ÃÂ· The indexers are usually known as smart arrays in C#.
ÃÂ· An indexer, also called an indexed property, is a class property that allows you to access a member variable of a class using the features of an array.
ÃÂ· Defining an indexer allows you to create classes that act like virtual arrays. Instances of that class can be accessed using the  array access operator.