Each has a different definition of public relations. For the purpose of this book, public relations means the management of a company's image through communication. It's about building reputations, developing relationships, creating a positive image, and informing and persuading people. It's different than advertising and marketing, which manage demand. These create or define a need and encourage people to seek a certain solution.
Advertising involves buying television or radio air time, or space in a newspaper or magazine.
Marketing conducts research about the public's attitudes. Marketers determine what people are thinking and what are the strengths and weaknesses of a company or organization's image. They use advertising or tools such as direct mail or brochures to address certain issues and concerns, thus creating a demand for a product or service. Both marketing and advertising are closely tied to sales and financial performance. Public relations is generally considered a more long-term program or investment.