Early television broadcasts were limited to live or filmed productions (the first practical videotape system, Ampex's Quadruplex, only became available in 1957). Broadcasting news, sports and other live events was something of a technical challenge in the early days of television and live drama with multiple cameras was extremely challenging. A live, 90-minute drama might require a dozen sets and at least that many cameras. Major set and other changes had to occur during commercials, and there were no "second takes." The cast and crew operated with the awareness of as many as 10 million people watching and any mistake went out live.