In word-of-mouth marketing, aka organic growth, there are 3 types of people that have a big impact:

Maven are the experts on a certain topic.

This is the person who knows everything about a certain topic.

eg. A smartphone maven

This person is the one that follows the new phones coming out and which features they have.

This person reads the spec sheet and understands it.

The type of processor they put into this phone is a bit more powerful than the previous version's, but the screen is a lot bigger so it won't be able to keep up. Oh and the battery capacity didn't improve that much either, so you'll probably have less hours with this phone. You should not buy the new model. But this new phone from this new company sounds really promising! I ordered it last month and it's really been great!

The example they gave in the book was about a soap maven. This is the person who reads the text on the soap's wrapper and calls the number when you have 'any further questions'.

You want to make a choice in a certain domain you know nothing about? You probably try to find a maven in your network.

Salesmen are people that are great at convincing you.

This is something you want.

This is the right choice for you.

maven may know what is the right thing for you.

But communicating that can be awkward.

Maybe communication skills are lacking.

Or they try to give you all information so you can make an informed decision.

(which is impossible, because you wouldn't want to know all information needed for that)

You want a recommendation to follow blindly.

Along with some clear reasons why this choice is perfect for you,

so you can convince yourself.

This is what salesmen do.

Social connectors are the people in the network that

know the strengths of people in their network

and can connect them when needed.

Someone may believe are a maven for a certain topic.

So you are asked for a recommendation.

But you are not at all that knowledgable about the topic.

Your friend on the other hand is.

So you introduce the two.

You were the social connector.

Did you translate the maven's responses to a more clear cut answer?

Did you leave out some of the potential negatives that are probably not that relevant?

Then you probably were a salesman as well as a connector.

Why is this model useful?

It helps to know which roles you can play when someone is asked for a recommendation.

Are they looking for a salesmen or a maven?

Can you be a social connector instead of taking on the burden yourself?

From a business perspective:

These three types of people are much more valuable to convince than random others.

How can you get them to know your product exists?

go to where they get their information

How can you convince Maven that your product is great?

free samples for early adopters, detailed specs page, add a 'contact for more detailed info', ...

How can you support Salesmen in advocating your product?

referral fees, ...

How can this model be useful to you?

(src: Book: The Tipping Point - Malcolm Gladwell)