Let's start with the Wikipedia definition -
Marketing is defined by the American Marketing Association as the activity, set of institutions, and processes for creating, communicating, delivering, and exchanging offerings that have value for customers, clients, partners, and society at large.  The term developed from the original meaning which referred literally to going to market, as in shopping, or going to a market to sell goods or services.
Sorry AMA but that's gibberish.
My definition - Marketing is creating, positioning, and growing your product or service (brand).
That's why I'm the writer and they aren't. In an effort to get everyone to think about their business in marketing terms here's what I do.
What are the elements of good marketing:
Positioning - What you bring to the market or the point of difference of your product or services compared to others in the marketplace. They used to call it the Unique Selling Proposition.
Aimee Stern and/or Stern Communications brand is expert in transforming complex information into marketing and communications campaigns that are accessible to all. I'm a writer who can strategize and market. (Most people can do one but not all three).
Branding - What does your company stand for and how do others define it? If you're doing it right they should be the same.
Public Relations - How, where and why you share information about your company and the service/product you offer. Includes broadcast, radio, print, online, social media, etc.
Advertising - Paying for visibility and placement in the above.
Competitive Intelligence - Knowing what your competitors are doing. In our case it's PR firms in the DC area who compete in the science, education and health arena. Making sure when I don't win an account I call them back and find out who did and why.
Pricing - Charging the right price for the perceived value of what you deliver to the markets you are in. And of course making a profit. A wise colleague once said to me - most people don't know the difference between good, excellent and mediocre. He was talking about writing. Many people will hire an average writer and think what they get is good. They also pay less.
If you are really good - and we are - then you charge more and raise the bar. It may cost you business sometimes (and in this climate that's hard to do) but it also means you know what you're worth and you don't cheapen it.
Distribution - How you get your products and services into the marketplace and to those who purchase and use them.
Research - Making sure you know who your customers are and keeping up-to-date on how what they want, need, purchase is changing in a world that moves at lightening speed.
If you think I'm wrong let me know.