Social media marketing refers to the process of gaining traffic or attention through social media sites. wikipedia.org

Search engine optimization (SEO) is the process of improving the visibility of a website or a web page in search engines via the "natural" or un-paid ("organic" or "algorithmic") search results. wikipedia.org

Pay per click (PPC) (also called cost per click) is an Internet advertising model used to direct traffic to websites, where advertisers pay the publisher (typically a website owner) when the ad is clicked. wikipedia.org

Internet marketing, also known as web marketing, online marketing, or e-marketing, is referred to as the marketing (generally promotion) of products or services over the Internet. iMarketing is used as an abbreviated form for Internet Marketing. wikipedia.org