Similar to search engine marketing, Social Media Marketing (SMM) differs in that it is paid advertising on social networks, not search engines. In essence they all work the same way although social marketing does have some advantages. For example social networks have much more accurate demographic data available which is perfect for targeting a very specific type of audience.
For example, Facebook has data about its user's age, location and relationship status. If you're a wedding photographer you can target women in your area that are engaged meaning your advertising is being spent on a very specific market, this is one of the big advantages of Facebook marketing.
Having used all of these sites from both sides of the coin has given us a great understanding of what works and what doesn't. Putting together an ad that works is great, putting one together that delivers maximum returns is advertising perfection and that's what we're all about, the maximum returns!