Search Engine Optimization, or SEO, is an internet marketing strategy, aimed at improving the visibility of a website on search engines - or in simple terms, making it easier for users to find the website, thus driving traffic, which eventually results in sales. This is achieved by making the website appear earlier in search engine results, and more frequently. To do that, optimizers need to know how search engines work, and what users are searching for.
Since searches can yield thousands or millions of results, search engines use complex algorithms to rank them. The results are ranked by how relevant and popular they are. Therefore, an optimizer's job is basically to convince the search engine that a website is popular and relevant - for example, by adding specific content to target keywords, or building backlinks to show to search engines that the site is authoritative and "popular."
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| The SEO process. Source: Whiteboard Creations |
When a user performs a search, the keywords they input determine what results are going to be shown. The more relevant a website is to the keywords, the higher it's ranked in the results (the sooner the user sees it). When looking for keywords, the search engines go through all text content of the website (including hidden content such as image tags) and the "meta" tags in the header of the document. Certain text fields are more important than others: for instance, titles - <h1> tags.
Usually, there is a lot of websites relevant to the same keywords, and the search engines need other factors in the algorithm of ranking. One such important factor is the number (and weight) of backlinks.
Backlinks are links on other websites that link back to the website which is being optimized. This is very important for search engines, since they assume that when others are linking back to a website (i.e. talking about it), it must be popular. Thus, the more backlinks it has, the higher it ranks.
In the past, the number of backlinks was the only considered factor, however this proved very easy to manipulate. Now, a much more important factor is the quality of a link. If the link comes from a small, new website without any traffic, it doesn't contribute much to rankings. However, if it comes from a high-ranked website that search engines consider popular and reliable, it is worth a lot.
Many other factors are involved in the ranking algorithm, such as social signals (most importantly, from Google+ pages), the age of the domain, or even how long the site takes to load, according to a survey by Moz.
KEYWORDS
In the ideal cases, SEO starts before the creation of the website - the initial step is keyword research. There are a few basic points to be made here.
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| Long Tail Keywords. Source: SEO Manchester |
General, short keywords yield millions or even billions of results, while more specific and longer ones narrow that number down. Therefore, with general keywords, a website has more competition; it is much easier to rank for a specific keyword. These are called long tail keywords.
For instance, the keyword "dog" yields about 1 390 000 000 results, and "Siberian Husky" yields 35 700 000 (about 400 times less). Thus, a website about Siberian Huskies is 400 times more likely to get a number-1 ranking than a website about dogs.
However, optimizers do not look just for specific keywords - they look for ones that have high traffic. Obvious high-traffic keywords have a lot of competition. A big part of an optimizer's work is to find keywords that have low competition and high traffic - these are SEO goldmines.
What users are actually looking for also has to be considered. If we take an online sport shoes store, for instance, trying to rank for the keyword "shoes" would be a waste of time. Even if high rankings are achieved, most of the traffic coming through would be users just browsing, with no specific goal in mind. However, ranking for "Nike Omega Flame size 42" brings in users with open wallets.
A popular myth is that search engines count each instance of a keyword, and the more times it appears on a page, the more it contributes to ranking. For this reason, many websites include articles which repeat the same word or phrase to a point that makes them incomprehensible. In reality, keyword density does not contribute to SEO at all and could only drive readers away from the page.
Moreover, search engines do not treat all text on a page equally. Keywords in title tags have a greater value - the closer the keyword is to the beginning of the title, the better. Keywords in text closer to the top of the page also bring more value than the ones placed further down. They should also be placed in image tags (which can bring in traffic from image search) and once in the URL. Keywords in the meta description tag do not contribute to rankings but should be placed there to attract users, as it is the snippet shown on search result pages (Moz.)
BACKLINKS
While keyword research and placement takes place while creating the website and content, building backlinks is what comes after. It is also a prominent part of an optimizer's job.
The most basic concept of SEO is that links pass "link juice." The juice amplifies with each next link.
There are countless ways to get backlinks. The most simple way is to create additional websites that linkback to the original website. However, this takes time, and the links are usually not worth much. A good idea is to create a blog that accompanies the original website, post on the blog regularly, and link back from the posts.
Another tactic is submitting content to large websites. One example is ezinearticles.com, where users submit text-based articles. There are also 2.0 websites, which accept images, video and other kinds of embedded media, such as squidoo.com. Some of these websites are specific - for instance, logo or infogrpahic submission sites. White papers and presentation can be submitted to slideshare.com, research papers can be posted on academic websites (whose links bring enourmous value). Writing testimonials, product reviews and commenting on blogs and forums are another way to build links, even though their value is much less.
Another popular tactic (which recently got beaten down) is guest blogging. Bloggers nowadays receive a staggering amount of guest-blogging offers and are starting to regard them as spam.
Optimizers also aim at getting organic backlinks, where other bloggers and webmasters wilingly link back to the website. There are many tactics to achieve this, marketing and PR skills are quite relevant here. This is called "link baiting." An example is creating a top 10 list, then sending the featured websites a badge. It is likely that they would put this badge somewhere on their website (to show it off) and link back. Jon Cooper explains such techniques in detail in his article Link Building Tactics - the Complete List.