In this edition of Something You Might Not Know About Canada, Olympic gold medal-winning swimmer Mark Tewksbury talked about the first use of instant replay on television.
CBC's Hockey Night In Canada was behind the experiment back in 1955.
"The producers filmed their own broadcast and played the resulting film back in slow motion," said Tewksbury. "Because they had to develop the film they could only watch the play back several minutes later. It was kind of like an eventual replay."