For all who wonder what Public Relations are
It’s not advertising, it’s not marketing
It’s an adapted and tailor-made budget

The key words
Credibility Reputation Strategy Communication

A definition
Public Relations are the practice of managing the flow of information between an organization (a company, a brand) and its publics (consumers, suppliers, opinion leaders). It is the planned and sustained effort to establish and maintain goodwill and mutual understanding between an organization and its target audience.

Credibility of Information 
Because public relations place exposure in credible third-party outlets (usually the media), it offers a third-party legitimacy that advertising does not have.

Food for thought
«The two most important things  in any company do not appear in its balance sheet: its reputation and its people.» Henry Ford, American Industrialist (1863-1947).