SEO stands for “search engine optimization.” It is the process of getting traffic from the “free,” “organic,” “editorial” or “natural” search results on search engines.

This is not a question with a general answer, as it really, truly depends on your current situation, objectives and marketplace. To better understand this question and understand the differences between SEO & PPC, check out this article on Search Engine Land.

A well-formed SEO strategy should always start with an Inbound GamePlan.  The Inbound GamePlan is a more flexible version of a traditional marketing strategy with a focus on shifting resources to the most measurable and effective inbound marketing strategies. The goal is to create a plan that will deliver the highest ROI for your business.

All SEO campaigns at Nacke Media start with an Inbound GamePlan. This article at HubSpot offers a good overview of the features of a good Inbound GamePlan.