SEO is free a traffic, a search engine displays your content in the search results when a search keyword matches with content in your website. While PPC is a paid traffic that comes to you from the keywords for which you have paid to your advertiser to display your contents on search results when someone use those keywords to search. In more single language its call advertising , see the image below when I searched Seo tool I get two different types of results.
SEO VS PPC Which is Better ?
Well, Seo has a lot of Advantages over PPC and SMM have a look at the Infographic.
Would you Invest on PPC or Optimize or business with Seo ? Do let us know.