As soon as you hear the term digital marketing the first thing that may instantly strike your mind is the word "digital"
and the first question that may arise in your mind is "what is digital marketing".
Now without talking any non-sense we will get straight to the point - The word digital is all about 
 which more or less means electronic signals and
so any medium that uses electronic signals (0,1)
can be termed as digital medium or electronic medium.
So digital marketing can be defined as marketing or promotion of brands,
products, services to the consumers by using any or all available forms of digital (electronic)
mediums like internet, mobile, television and radio. This is the reason why digital marketing
is also known as electronic marketing or simply e-marketing.
SEM: Search Engine Marketing
Search Engine Marketing (SEM) is basically the science and art of getting
targeted traffic (free and paid) to your website from Google,
Yahoo, Bing or other search engine networks. In other words search engine
marketing can also defined as a form of internet marketing that involves
the promotion of websites by increasing their visibility in the search engine
networks through all the activities that bring the free targeted traffic from
search engine networks (Search Engine Optimization) and all the activities that
bring the paid targeted traffic from search engine networks (Search Engine Advertising)
SEO: Search Engine Optimization
Whenever you type a query in any search engine and hit the "search" button
you get a list of web results called organic
(unpaid or natural or free or algorithmic) search
results which contain that query term. Users normally
tend to visit the websites that are at the top of this
list as they perceive those to be more relevant to the query.
If you have ever wondered why some of these websites rank
better than the others then you must know that it is because
of a powerful internet marketing technique called SEO that
basically stands for Search Engine Optimization and is an important
part of SEM as well.
SMM: Social Media Marketing
In analogy to search engine marketing explanation
we can similarly state that Social Media Marketing
(SMM) is basically the science and art of getting
targeted traffic (free and paid) to your website from Facebook,
Twitter, LinkedIn, YouTube, Google+ or other social media networks.
In other words social media marketing can also defined as a form of
internet marketing that involves the promotion of websites by
increasing their visibility in the social media networks through
all the activities that bring the free targeted traffic from social
media networks Read more...
SMO: Social Media Optimization
Social Media Optimization (SMO) is the science
and art of getting free targeted traffic to your
website from Facebook, Twitter, LinkedIn, YouTube,
Google+ or other social media networks through various
social activities like blogging, posting status updates
on social media profiles, participation in discussion groups,
social bookmarking, virals, online reputation management,
user rating/polling, user feedback, RSS feeds, sharing buttons,
use of video/photo sharing sites and many more.
Internet Marketing: Online Marketing
Internet is one of the biggest and cost
effective digital medium available worldwide.
Internet Marketing can be defined as marketing
or promotion of brands, products, services to
the consumers by utilization of internet as a
digital medium. When we say that we are online
then it simply means that we are using internet
or in other words accessing the world wide web
and so internet marketing is also known as online
marketing or web marketing. Moreover the word iMarketing
is also used as an abbreviated form for internet marketing.