Advertising is the practice of creating public messages designed to persuade people to buy products, support ideas, or take specific actions. When a company makes a commercial for a new cereal or puts up a billboard for running shoes, that's advertising. The goal is to catch your attention and convince you that you want or need what they're offering.

Advertisements appear everywhere: on websites, in magazines, on television, on buses, and even on the jerseys of athletes. Companies pay money to place these messages where people will see them. A clever advertisement might make you laugh, tell a story, or show happy people using a product. The best advertising makes products memorable, which is why you might find yourself humming a jingle from a commercial or remembering a catchy slogan years later.

Behind every advertisement is an advertiser, the person or company paying for the message, and often an advertising agency, a business that specializes in creating effective ads. The advertising industry employs writers, artists, psychologists, and strategists who study what makes people pay attention and what influences their choices.

Understanding advertising helps you think critically about the messages you encounter daily. When you recognize that someone is trying to sell you something, you can decide for yourself whether you actually want or need it.