Advertising
Advertising is an audio or visual form of marketing communication that employs an openly sponsored, non-personal message to promote or sell a product, service or idea. Sponsors of advertising are typically businesses wishing to promote their products or services. Advertising is differentiated from public relations in that an advertiser pays for and has control over the message. It differs from personal selling in that the message is non-personal, i.e., not directed to a particular individual. Advertising is communicated through various mass media, including traditional media such as newspapers, magazines, television, radio, outdoor advertising or direct mail; and new media such as search results, blogs, social media, websites or text messages. The actual presentation of the message in a medium is referred to as an advertisement or "ad" for short.
Marketing
Marketing is the study and management of exchange relationships. Marketing is used to create, keep and satisfy the customer. With the customer as the focus of its activities, it can be concluded that Marketing is one of the premier components of Business Management - the other being innovation.
Psychology
Psychology is the science of behavior and mind, including conscious and unconscious phenomena, as well as feeling and thought. It is an academic discipline of immense scope and diverse interests that, when taken together, seek an understanding of the emergent properties of brains, and all the variety of epiphenomena they manifest. As a social science it aims to understand individuals and groups by establishing general principles and researching specific cases.
Psychology
Despite the burgeoning technologies in the field of "helping", on many levels psychotherapy is still a crapshoot. Some of the goal of training, I think, is to help students accept that fact. The work is part science, part art, and part luck. Learning to tolerate the anxiety inherent in that recipe is critical for any clinician.
Martha Manning, in Undercurrents (1st edition ed.). HarperCollins. 1995. pp. p. 9