marketing | Marketing covers the strategic planning and tactical execution of initiatives that generate interest for an idea, product or service, providing the optimal combination of value and utility for the end user in a captive market.
 
A properly executed marketing campaign blends effective messaging with creative appeal to promote, brand, or position products and services to motivate a sale.

advertising | An advertisement is a form of sponsored communication placed in print, web, radio, television or other mass media with the intention to generate popular interest or brand appeal for an company's idea, product, service or brand.
 
Linked directly to marketing and public relations, it aims to build the image and perception of a product supported by marketing strategies and publicity tactics.

public relations | Publicity is another strategic element of the promotion mix that aims to motivate public interest by exerting influence over the perception a market has about a brand, company or product.
 
Publicity builds a relationship with the audience through press or media coverage, news articles, media plugs or market buzz for little or no cost.