There are so many answers to both those questions. I consider internet marketing to be all about promoting your chosen products and companies online, and branding yourself to be a coach and mentor to others who want to make money online. You could choose a hundred different avenues to earn via internet marketing. For myself personally, I only go for things that I know are genuine and will actually help others - i.e no ridiculous overpriced e-books or get rich quick schemes that promise much and deliver little. Affiliate programs are where it's at for a lot of people, but like I said - you need to find the ones that will work for you and others will be interested in. Being a newbie, I can't post any links in my signature, but you're welcome to check out my official blog in my profile - I talk about the best free and low cost programs and ways to make money online. Good luck
I think this is one of the best resources helping to clarify what internet marketing is http://en.wikipedia.org.wiki/Online_marketing
The unique benefits of on-line marketing marketing are lower costs for the distribution of information and media to a global audience, providing instant response and eliciting responses
You must know some knowledge about the internet. Different ways on how to advertise your services online.