Inbound marketing is a style of marketing that focuses on getting found by customers. With this kind of marketing you can "publish your way in" not opposite way by "buying your way in". It is like relationship marketing or permission marketing where you do not have to compel people to buy your products or services. With Inbound marketing people will find you because they want to and more likely they will buy from you.

Outbound marketing (traditional marketing):
trade shows, printed advertising, telemarketing, direct mail, mass email, television advertising, cold calling, online advertising, etc.
Outbound marketing could be disdurbing! For example, if you do cold calling. In that case you:
1) do not know who is this person you are talking
2) do not know what is his/her prioritys, wishes, desires, etc.
3) may disturb him/her on that moment where they do not want to be disturbed...maybe they have been working all night and have just arrived home and fallen a sleep...do you like to be disturbed on that time?
4) I could go on and on, but I think you have already understood why cold calling is not so effective anymore.

Nowadays we have much greater opportunities to find products that we want to buy, not products that someone else want us to buy! So does our customers have much variable choices and with inbound marketing we can bring people to us in a way that they want, not the way we want and that is much more agreeable way to both parties.

Inbound marketing (alternative marketing):
Search engine marketing, blogs, search engine optimization, social media, building relationships, publishing quality content, viral marketing, letting customers find you, becoming a resource, creating a community, etc.
But how to do that?! I am sure that most of WA users already know that and are faliliar with this, but not all of us, that is why I will create a short overview of it. So, lets get started:)