Is The Universe Infinite?

All of us have been curious on the universe to whether it has its ending or it's somewhat like the "Pi" in mathematical equation?
Various studies have been made due to its mystery and obviously, these researches are still at large until it answers our questions about the infinite blackness of the universe. Without proper equipment and technology, there will be lack of results in all the research.
But since humans are intelligent enough to invent and discover more of the advanced technologies, then there might be answers to our questions. One theory explains the billions of galaxies scattered everywhere is the Big Bang theory, to which it's mentioned in this video why it was called the "Big Bang" theory.
But, is the universe infinite?