W5 is a Canadian news magazine television program produced by CTV News. The program is broadcast Saturday nights at 7 p.m. on the CTV Television Network, with repeat broadcasts at later times on CTV as well as co-owned channels CTV 2, and Investigation Discovery. The program also airs in a radio simulcast on CFRB (1010) in Toronto. The title refers to the Five Ws of journalism: Who, What, Where, When and Why? It is the longest-running newsmagazine/documentary program in North America and the most-watched program of its type in Canada.