Definition of "Happen" :
verb: come to pass
"What is happening?."
verb: come into being; become reality
verb: happen, occur, or be the case in the course of events or by chance
"It happens that today is my birthday."
verb: come upon, as if by accident; meet with
"I happened upon the most wonderful bakery not very far from here."
verb: chance to be or do something, without intention or causation
"I happen to have just what you need!."