Search engine optimization (SEO) is the practice of increasing the quantity and quality of traffic to your website through organic search engine results.
What does SEO mean?
To understand what SEO really means, let's interrupt that sentence and look at the parts:
Quality of traffic
You can attract all visitors to the world, but if they come to your site because Google tells you that you are a source for Apple computers, while in reality you are a farmer selling apples, it is not quality traffic. Instead, you want to attract visitors who are genuinely interested in the products you offer.
Amount of traffic
Once you have the right people who click through from search engine results pages (SERPs), more traffic is better. Organic results. Advertisements form a significant part of many SERPs. Organic traffic is traffic for which you do not have to pay.
Organic search traffic is in particular all the unpaid traffic that comes from SERPs.
How SEO works
You could see a search engine if a website you visit to type a question into a box (or speak) and Google, Yahoo !, Bing or whatever search engine you use magically answers with a long list of links to Web pages that may answer your question.
That's true. But have you ever stopped to think about what is behind those magic lists of links?
This is how it works: Google (or another search engine you use) has a crawler that visits all websites and collects information about all the content they can find on the internet. The crawlers bring all that information back to the search engine to build an index. This index is then executed using an algorithm so that the data tries to match your question.
There are many factors that contribute to the search engine algorithm, and here is how a group of experts ranked their importance:
The SE (search engine) of SEO
The O part of SEO optimization is all the content of what people write on their sites, send through their sites in a certain way, so that search engines can understand what the content is and the users who are looking for something find what they are looking for. Optimization can take many forms. It is to ensure that the title tags and meta descriptions are both informative and the correct length and to refer internal links to pages that you want visitors to be directed to.