Marketing in common parlance is roughly equivalent to "selling". However Marketing as an academic discipline involves vocational training many other areas of business, such as advertising, public relations, product design, pricing, distribution, sales force management, and so on.
In academia the term "Marketing" is often synonymous with the "Marketing Concept", which is a general business philosophy. Marketing scholars hold that the historical development of business "orientations" started with the "Production Orientation", which can be briefly described as "make (i.e. manufacture) as much as you can, and someone will buy it." This was replaced by the "Selling Concept" which can be summarised as "People won't buy things by themselves, you have to get out there and sell it to them." Implicit in both these orientations is that businesses decide what to produce, and how much to produce is determined by production capacity or sales-force performance, respectively. The "Marketing Concept" replaces these ideas with something along the lines of "First, find out what people actually want, and then organise ourselves to deliver it." It can be paraphrased simply as "The Customer is King." Note that in the Marketing Concept it is consumers who drive what and how much is to be produced.