title	Unions
intro	A union is a type of object representing many objects.
redirect_from	/v4/union /v4/reference/union
versions	fpt ghec ghes * * *
autogenerated	graphql
category	Explore the schema reference

About unions

A union is a type of object representing many objects.

For example, a field marked as an ProjectCardItem could be an Issue or a PullRequest because each of those objects can be inside a project card. Using a union instead of an object gives you flexibility.

For more information, see AUTOTITLE.