Digital marketing is a way of promoting your products through the digital media such as Mobile, Television, Internet, etc.. This include many of the techniques within the category of Internet Marketing. Digital marketing is much more successful and effective. Digital Marketing strategies must be allocated for SEO and SEM.. A common factor overlooked by many companies is that in most cases 80% of their business is likely to be generated by approximately 20% of the keywords they are targeting. You can look into http://hiox.org/11374-digital-broadcasting.php
Digital marketing entails the development of strategies to engage and interact with the audience and your potential customers. It includes making sure your online e-commerce platform (online store) is easily navigable, accessible and is consistent with the image of your brand. It also includes monitoring the conversations that people are having about your brand or products online to understand how people perceive your company. Another important factor is to interact with the customers either through social network presence or a blog that provides relevant and responsive content. In terms of SEO (search engine optimization), it is about coding your websites and landing pages in a way such that it can come up on Google or Yahoo or Bing when people type in the correct search words. For example, if you type in "Electronics" to your search engine, companies like Best Buy, Sony, Radio Shack, etc. will want to make sure they at least appear somewhere on the first page. The way to do this is to optimize your keywords (positive and negative ones) so that you are the most "relevant" search result. Some companies like to pay for this, which is why you see "Sponsored Results" at the top of the Google search page. When you start paying to do this, it is called SEM (search engine marketing). Hope this helps!
What every one does that includes different technological mediums is digital marketing. It is called digital marketing as our world today is bound with new digital forms and ways to promote, entertain, advertise, and many more.