What is SEO and its types?

Search Engine Optimization – #SEO is the art and science of optimizing your web pages to be found by the search engines like Google, Yahoo, and Bing etc.
But why part art, part science? The science part of Search Engine Optimization (SEO) deals with technology and all the engineering & technicalities of a website such as code, information architecture & user experience etc.
There are two ways of optimization:
On-Page SEO - It includes providing good content, good keywords selection, putting keywords on correct places, giving appropriate title to every page, etc.
Off-Page SEO - It includes link building, increasing link popularity by submitting open directories, search engines, link exchange, etc.
SEO techniques are classified into two broad
categories:
White Hat SEO - Techniques that search engines
recommend as part of a good design.
Black Hat SEO - Techniques that search engines do
not approve and attempt to minimize the effect of.
These techniques are also known as spamdexing.
White Hat SEO
An SEO tactic is considered as White Hat if it has the
following features:
It conforms to the search engine's guidelines.
It does not involve in any deception.
It ensures that the content a search engine indexes,
and subsequently ranks, is the same content a user
will see.
It ensures that a web page content should have
been created for the users and not just for the
search engines.
It ensures good quality of the web pages.
It ensures availability of useful content on the web
pages.
Always follow a White Hat SEO tactic and do not try
to fool your site visitors. Be honest and you will
definitely get something more.
Black Hat or Spamdexing
An SEO tactic, is considered as Black Hat or
Spamdexing if it has the following features:
Attempting ranking improvements that are
disapproved by the search engines and/or involve
deception.
Redirecting users from a page that is built for
search engines to one that is more human friendly.
Redirecting users to a page that was different from
the page the search engine ranked.
Serving one version of a page to search engine
spiders/bots and another version to human visitors.
This is called
Cloaking SEO tactic.
Using hidden or invisible text or with the page
background color, using a tiny font size or hiding
them within the HTML code such as "no frame"
sections.
Repeating keywords in the metatags, and using
keywords that are unrelated to the website
content. This is called
metatag stuffing.
Calculated placement of keywords within a page
to raise the keyword count, variety, and density of
the page. This is called
keyword stuffing.
Creating low-quality web pages that contain very
little content but are instead stuffed with very
similar keywords and phrases. These pages are
called
Doorway or Gateway Pages.
Mirror websites by hosting multiple websites - all
with conceptually similar content but using different
URLs.
Creating a rogue copy of a popular website which
shows contents similar to the original to a web
crawler, but redirects web surfers to unrelated or
malicious websites. This is called
page hijacking.
Always stay away from any of the above Black Hat
tactics to improve the rank of your site. Search
engines are smart enough to identify all the above
properties of your site and ultimately you are not
going to get anything.

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