If you've advertised at all on Facebook, I'll bet you're already familiar with interests targeting.

This is arguably the most important and useful targeting feature available to advertisers.

Why?

Because with interest targeting, Facebook accesses pretty much each and every piece of information you've posted on your timeline. Unlike other targeting options, where Facebook uses information you've provided when you signed up and first set up your profile (or timeline), interests can be pulled from:

-- Your likes & interests

-- Pages you're a fan of

-- Groups you're part of

-- Apps you use

-- Education

-- Job title

-- Other content you've provided on your timeline.

While Facebook doesn't currently pull interests from your status updates, one can only imagine this will happen in the future.

Precise Vs. Broad Interest Targeting

You can choose to use either precise interest targeting or broad interest targeting:

When you start to type in a precise interest, you'll notice some start with a hashtag (#) and some don't. For example, you could choose to target actual fans of McDonald's page (under Precise Interests, no hashtag), or anyone indicating McDonald's as an interest (and not necessarily a fan of their official page), by selecting #McDonald's.

By choosing #McDonald's, you'll noticed I get a much higher potential reach than when I select McDonald's (no hashtag), so be sure you have a good reason for it if you're going to select a precise interest.

Facebook pulls these suggestions from the profiles (timelines) of those who like the interest you've already selected (much like Amazon's 'Other uses who bought this also viewed' feature). This can be a great way to expand your reach to related interests you may not have thought of.

When you switch to broad category targeting, you'll get an actual list of interests you can choose to target. This is a great option, especially if you're new to Facebook advertising and want to see the options available to you.

This will pull interests from across users' timelines, not just fan pages they belong to. This is a great option for more general targeting. Note that broad and precise interest targeting are mutually exclusive - you have to choose one or the other.

It's also important to note that selecting multiple broad interests will target users with ANY of those interests, not ALL of them (for instance if you selected soccer and basketball, it would target users who like soccer or basketball, not soccer AND basketball).

Next week we'll conclude this series on Facebook targeting with targeting by education and connections. Stay tuned!