A commercial is an advertisement for your product or service. It usually has a limited duration – 15 seconds, 20 seconds, 30 seconds, 45 seconds or even 60 seconds. The longer your commercial the more you must pay the network to air it. In the days before the Internet, TV Commercials were really the only way to reach you target segment. These commercials were aired on various television channels, in various time slots and in-between programmed content. Based on the kind of programmed content and time slots, brands could target their customers. So for example, a washing machine detergent brand may choose an afternoon slot during soaps, since these shows are likely to be watched by housewives. A life insurance company may choose to air its commercials at Prime Time during news and sports shows, since the target audience would be working men. Now, YouYube Pre-rolls have started acting as TVCs in the internet world. You can reach your target audiences before they watch a piece of content.