Each of the main characters in Smallville discovered the truth about Clark Kent (Tom Welling) being Superman at very different times in the series. Like most superhero stories, one of the most important elements of Smallville was Clark's secret identity. Since the pilot episode, Clark tried to protect the secret of his powers and his Kryptonian heritage from the people around him, but there were times when Clark either failed to hide the truth or was compelled to come clean.
