What is Search Engine Optimization (SEO)?
Before going into deeper aspects of search engine optimization (SEO); it can be defined as the process of improving performance of a website or a
web-page, by optimizing various elements of a site (on-page and off-page) to achieve the highest
possible ranking in search engine results pages (SERPs) of the major search
engines such as Google, Yahoo, and Bing, among others.
Moreover; achieving the highest rank in the SERPs of these search engines is not enough for one to achieve their website marketing goals, which may be to generate more web-traffic, to increase sales, to get visitors download a given product, to get subscribers, etc etc; and one will only achieve all these goals when they can convince searchers to click-through to their site by making good use of keywords in the descriptions and titles to give searcher more reasons why they should visit your site and execute the expected action.
At this point; SEO can be so overwhelming when it is not planned for properly: It is important to understand that SEO is very broad, and can be separated into two major parts that can be effected separately: Organic SEO and Plain SEO.
The first part of SEO is referred to as organic SEO or real SEO; which is a free (non fee-based) means that site owners who are SEO purists utilize in order to naturally achieve a higher website ranking on SERPs, and consequently generate a free website traffic from automated and page-indexing search engines such as Google, Yahoo, and Bing.
The second part of SEO is known as advanced SEO or plain SEO (also referred to as search engine marketing or SEM; which is a mixture of organic SEO and fee-based marketing techniques such as keyword advertising through paid searches or advertising programs for example pay per click; and modern marketing techniques that allow marketers to collect and analyze consumer-based data for more positive results.
Get me right here; to succeed with your SEO efforts and sustain the stiff competition that exists on the internet; both organic and fee-based marketing are a necessity. Fee-based SEO alone is always ineffective without organic SEO; which is embraced a lot by website owners since it's a free long-term internet marketing strategy that will be
productive for years in terms of site ranking, traffic, and goal conversion when formed as per the requirements of the major
search engines such as Google.
On the other hand; due to the stiff competition, one cannot make it with organic SEO alone without involving in fee-based SEO techniques such as keyword advertising through paid searches and other marketing platforms such as social media. As such a combination of both is recommended for an impressive website performance and returns.
Finally; there are a number of search engines today as you can see in the diagram at the bottom of this page: Each search engine has its own set of search algorithms; which determine sets of quality scores of a given web page before showing relevant web-pages in the SERP, depending on keywords or a phrase that users type in the search box.
As such; before starting SEO process for a given site, ensure that your SEO strategy either targets a specific search engine, or all search engines depending on your SEO goals. If you're hire an SEO expert, be certain that he/she understands the criteria and major ranking factors that the search engine(s) you are targeting uses to rank web-pages in the SERP. Since Google is the biggest search engine; here are among sets of Google quality scores that a web-page must meet in order to rank high on Google's SERP.
Google SEO: How to Optimize your Web-pages for Google's Search Engine