What is the union in C?

C Union. Union is an user defined datatype in C programming language . It is a collection of variables of different datatypes in the same memory location. We can define a union with many members, but at a given point of time only one member can contain a value.

A union is a user-defined type similar to structs in C except for one key difference . Structures allocate enough space to store all their members, whereas unions can only hold one member value at a time.

Structure is the container defined in C to store data variables of different type and also supports for the user defined variables storage. On other hand Union is also similar kind of container in C which can also holds the different type of variables along with the user defined variables.