These two terms are often used interchangeably. But, they have significantly different meanings.
American Heritage Dictionary defines Marketing as:
"The commercial functions involved in transferring goods from producer to consumer"
Whereas Advertising is defined as:
"To announce or praise (a product, service, etc.) in some public medium of communication in order to induce people to buy or use it"
I once had an economics teacher that to used to harp on the difference between these two terms. So what? Who cares? When we speak, don't we inherently understand what the other party is trying to communicate to us? Well, yes and no. I will admit, I'm a bit of an "English Police". I hate it when someone butchers the language verbally or in print, so keep that in mind as you read this post. But my feelings are this...if you misuse the language, it can make you appear uneducated. If you appear uneducated, it can diminish the trust between you and your client. So, it's my goal to always speak and write in a manner that makes me sound the best.
Let's not confuse these two terms when talking to our client or in producing promotional products for our business. In Real Estate we market ourselves or our services, but we advertise our listings.