Explain what are Unions?

The Unions like as structures, contain members whose individual data types may perhaps differ from one another. Though the members that create a union all share the same storage area within the computer's memory, whereas every member within a structure is assigned its own unique storage area. Therefore the unions are used to converse memory and they are useful for applications involving multiple members where values require not be assigned to all of the members at anyone time.

Within a union, the bookkeeping need to store members whose data types are different (having different memory requirements) is handled automatically by the compiler. Though the user must keep track of what type of information is stored at any given time. An effort to access the wrong type of information will produce meaningless results.