Digital marketing is often referred to as 'internet marketing', 'online marketing' or 'web marketing. Digital marketing is marketing activities which includes search engine marketing (SEM), search engine optimization (SEO), social media marketing, social media optimization, content marketing, influencer marketing, campaign marketing, and e-commerce marketing, e-mail marketing, display advertising and any other form of digital media. It also extends to non-Internet channels that provide digital media, such as mobile phones (SMS and MMS), callback and on-hold mobile ring tones.
Search Engine Optimization (SEO)- is a process of increasing visibility of website through On page optimization and off page optimization.
Social Media Optimization (SMO)- is the use of a number of social media outlets and communities to generate publicity to increase the awareness of a product, brand, article or event
Search Engine Marketing (SEM)- is a parts of internet marketing which used to increase website visibility in search engine results pages (SERP) . SEM incorporates Search engine optimization and pay per click (PPC)
Pay Per Click (PPC)- is also known as CPC (Cost per Click) PPC is a model of internet marketing in which advertisers pay a money each time their ads is clicked. It's a way of buying visits to your site, rather than attempting to earn those visits organically.