I have a pet peeve that some of you may consider strange. Well, I have a lot of weird pet peeves, but I want to address one in particular, and that's the way people use "marketing" when they mean "advertising." (I also have a huge pet peeve about the design of public restrooms, but that's a story for another time.)
Let me set you straight (if you confuse or conflate these words). Advertising is about trying to persuade your audience/constituency/customer base/patrons to partake of your services, to get to know you and your services better. Marketing is almost the opposite - it's about you getting to know your target audience better and learning what kinds of products/services/etc. they need &/or want. Both advertising and marketing are about raising awareness, and both can be done at the same time, but they really are distinct activities because of their end goals.
Why do I bring this up here on a blog geared towards librarians? Besides how rampant the misuse of these words seems to be in our profession, I mean. I'm bring it up here because I'm a fan of precision in vocabulary and the way precision can help you understand what you're doing so you can do a better job of it. The truth is that libraries need to market as well as advertise, but we're not as good at the former as we are at the latter. Librarians love to talk about libraries, but we don't really like to listen. And trust me, we need to listen to our customers if we want them to listen to us.
A perfect example of the difference is how some companies handle social media. Are you engaging with your customers? Answering their questions, retweeting things they say about you? Or are you you doing all the talking? The same goes for in person communication - other than collection development suggestions, how often do you really listen to your patrons? Besides, advertising can be so much more effective if you've done a little marketing first.
Perhaps I'm being a bit pedantic here, and I'm willing to own up to it. If I'm going to be honest, I'll admit it doesn't matter as much what you call what you're doing, so long as you are talking with as well as listening to the people who come to your library.