Union is derived data type contains collection of different data type or dissimilar
elements. All definition declaration of union variable and accessing member is
similar to structure, but instead of keyword struct the keyword union is used, the
main difference between union and structure is each member of structure occupy the memory location, but in the unions
members share memory. Union is used for saving memory and concept is useful
when it is not necessary to use all members of union at a time.
Where union offers a memory treated as variable of one type on one occasion
where (struct), it read number of different variables stored at different place of
memory.
