Worldwide, advertising is a billion-dollar industry, with nearly $500 billion spent in 2016. That industry includes the companies that place advertisements, the agencies that create them, and the media that runs them.
A really good advertisement isn't easy to make. Companies sometimes hire agencies to solve this problem for them. Advertising agencies write, design, and create the advertisement. Today, advertising agencies create all sorts of ads that go on TV, in magazines, across the bottom of mobile apps, or on the sides of buses. But not all companies use advertising agencies. Some hire creative people to work at the company and write, design, and create ads just for that company, year-round.
Once an advertisement is produced, it will be passed on to a media company who will then run the advertisement. When a media company runs an ad, it ensures that viewers have to see the advertisement. That is why magazines have full-color photos of new bags to purchase and the Super Bowl plays commercials in the middle of the game.

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