Search Engine Optimization Linking Strategies
Hyperlinks are critical factors in achieving high search engine rankings. Many elements from the number of inbound page links, HTML coding, and linking patterns play an important roll in an optimum linking strategy.
In the early days of search engine optimization, only on-page factors were important for determining placement. However, as search engines looked to enhance their [[SERP]]s and filter spam they started looking at [[inbound links]] as a measure of the importance of a website.
Now it is critical for a website to combine on-page factors with having a significant number of optimized inbound links and proper internal linking to achieve top search engine rankings.
This article is a tutorial for proper hyperlinking strategies.
Anatomy of a Standard Hyperlink
A basic hyperlink - also called an anchor tag - is as follows:
Link:
LevelTen Web Design
- Professional Website Designers
HTML Code:
LevelTen Interactive
Link:
HTML Code:
The words between the opening and closing "a" tags are what is displayed on the page and is called the anchor text. Notice in the second example the text is replaced by an image link. In this case, the alt attribute of the img tag substitutes for the anchor text.
The href is the url that a browser will navigate to when the anchor text is clicked. The anchor text and href are the two most important parts of a hyperlink as far as search engines are concerned.
The only other significant part of a hyperlink for SEO purposes is the "title" attribute. The title attribute is used to provide a more verbose description of the link. Most browsers will display the title as a [[tool tip]] when the mouse rolls over the link. Some search engines factor in the title for ranking purposes.
Some search engines will also consider the words around a hyperlink called surrounding text. In the examples above "Professional Website Designers" would be surrounding text. While technically not part of the hyperlink, most experts theorize that surrounding text plays a role similar, although less significant, to anchor text.
There are many other attributes that can be assigned to an anchor tag such as "target" to tell the browser where to display the linked page, "class" to reference styling of the link, "name" or "id" for identifying the link for scripting, and many more. However, these attributes have little impact in how a search engine uses the link.
Scripted Links
Another popular way for a web page to link to another is scripted hyperlinks. These are often called JavaScript links, yet can be in any client side scripting language, such as JScript or VBScript. Examples of scripted links are:
Link:
LevelTen Web Design
HTML Code:
LevelTen Design
Alt HTML Code:
LevelTen Design
Scripted links are most often used in three scenarios: pop-up windows, AJAX, or DHTML navigation.
A scripted link offers more control over a pop-up window than a standard hyperlink. Web designers often use scripted links to control the size, menus, scroll bars, and other attributes of the opening window.
Many forms of advanced navigation, such as drop-down menus, often require DHTML and scripted links.
Several other types of scripted links are popular, such as Flash navigation and Java Applets.
The reason it is important to distinguish between standard and scripted links is that most search engines do not read scripted links. In other words, most search engines treat a scripted link as no link at all. Most likely in the future search engines will add the ability to read various types of scripted links, but for now it is important to avoid them when you want a link to be read by a search engine.
If your site is AJAX based, it is best to use [[unobtrusive JavaScript]] techniques. An unobtrusive AJAX link would be embedded in the server generated page markup as a standard hyperlink. Then JavaScript would bind the AJAX version of the link when the [[DOM]] has finished loading. This way the search engines have a standard link they can spider, AJAX will work correctly if the browser supports AJAX and degrade gracefully to standard navigation if the browser cannot support AJAX.
URL Types
Many different ways exist for referencing web pages. The standard is a simple static page, referenced as fileName.html or fileName.htm.
More sites are using dynamic pages which typically use parameters passed in a query string to generate content. For example:
scriptName.php?pg=contact
A query string is anything after the "?" in a url. Query strings contain key value pairs that provide web script parameters. In the first example, the site may be pulling content from a database and the "pg=contact" would tell the script to return the contact us page. The second example is typical of a shopping cart where categories and products have numbered indexes.
Most search engines can read URLs with query strings and will include, or "index", them in their database. However, the more complex a query string is the less likely it will be indexed. In particular, if a query string includes a session ID most search engines will have trouble indexing the page.
External vs. Internal links
Internal, or relative, links are hyperlinks from web pages on the same domain. For example http://www.yoursite.com to http://www.yoursite.com/contact.html. External links are hyperlinks from other domains to yours, e.g. http://www.theirsite.com to http://www.yoursite.com.
Search engines will look at both internal and external links when ranking a web page, yet each search engine will most likely weigh them differently. Internal links generally help as a measure of the size of a site and how important the web developer feels a page is in their own site. External links are used as a factor of how important others feel a site is.
Big Spiderable Sites
Since you have the most control over internal linking it should be where you start your linking strategies. Your goal is to have as many pages as possible of unique content indexed by the search engines.
The first issue that must be addressed is: are your hyperlinks spiderable? E.g. how many links on your site will a search engine spider follow? From an SEO viewpoint, having many pages on your site that the search engines can not find is futile.
Spiders can always follow standard hyperlinks to standard URLs. When possible use standard styles of linking. When you must use more complex linking, be aware of problem areas. Search engines will not parse most scripted links. Links to query string style URLs may not be indexed if the query string is too complex.
Fixes for un-Spiderable Links
If your site contains scripted links that search engines can not spider, then provide alternative standard hyperlinks elsewhere on the page that can be spidered. One way to do this is to include duplicate navigation using standard hyperlinks. You will see many websites include a second set of links at the bottom of a page. Another popular way is to provide a site map. A site map is a web page that includes standard links to all pages on your site.
A site that is not spiderable because of complex URLs presents a bigger problem. Often the only way to fix the complex URL problem is to switch to a technology that uses simpler query strings. Whenever you are selecting a technology for dynamic web pages, e.g. content management systems, shopping carts, etc., look for those that have simple query strings and do not require session IDs.
Optimizing Your Links
Now that you have spiderable links you want to optimize them. The most important method is to put the keyword phrase that you want to enhance the ranking for on the linked to page in the anchor links. You can do this as text or by utilizing the alt tag for an image link. You may also want to include a title tag with the keywords.
It is very important to make your links user friendly and consistent. Always try to maintain the integrity of your site when selecting anchor text. For example, menu links should normally have short phrases, such as "products", not necessarily long chains of keywords such as "affordable widgets in Dallas, Texas." However, you can often hyperlink body content that does have the keywords in it.
For example, in the body of a page you might have:
Acme widgets specializes in affordable widgets in Dallas, Texas. We pride ourselves in our service...
Just remember, always try to get keywords in links, but do not go overboard.
Linking Topology
Linking Topology is the mapping of how the pages of your site are interlinked. Often some pages in a site have fewer incoming links than others. For SEO purposes, the more inbound links a page has from pages that have fewer outbound links, the higher it will rank in the search engines.
For example, in the site:
- Home
- Products
- Category 1
- Widget A
- Widget B
- Category 2
- Widget C
- Widget D
- Widget E
- Category 3
- Widget F
- Category 1
- Contact
A typical way to link the main menu would be:
Home Page:
|
Products Page:
|
Catagory 1 Page:
|
In this scenario, the Home, Products, and Contact pages would get the biggest linking boost because every page in the site links to them. However, this would not be a good strategy if your goal was to get good rankings for a term on the Widget A page.
So what do you do if Widget A is a popular search? You could show the entire linking tree on all pages. This causes a problem because now every page has so many outbound links it dilutes the value of each; also this might confuse visitors by presenting too many choices. You could expand only the Category 1 links, so that all higher level pages have the "Category 1 Page" menu links. To visitors though, it would seem you are favoring the Category 1 products. If the weighing is logical - great - but often visitors might be turned off by perceived inconsistent navigation.
Often you have to get creative. One great trick is to put a "Featured Products" sidebar on every page that links to the Widget A page. In addition, this makes marketing sense because you highlight a popular product and maintain logical navigation.
External Links
Basically, the same rules apply to external links that apply to internal links. You want links from popular pages on other sites that do not have many other hyperlinks and you want your targeted keywords in the anchor text and surrounding text. There is some evidence that search engines even consider the overall topical theme of an external website. Therefore, if you are in real estate a link from another real estate related site would be worth more than the same link on a non real estate related site.
The number of links you have to your site is called link popularity. In other words, how popular does the rest of the web think your site is. One of Google's key ranking factors is Page Rank which modifies standard link popularity to weigh how much link popularity the page that is linking to you has.
In general, the search engines weigh external links higher than internal links because it is a measure of another's opinion of your site. The theory goes, if your site has valuable and/or unique information then people will link to you. External linking is so important that some search engines will drop you out of their database if they can not find enough external links to your site.
Another important benefit to external links is that search engine spiders will follow those links to your site. The more often spiders find your site, the faster you will be added to the database, and the quicker any site changes will be updated.
Aside from search engine ranking external links benefit your site by exposing your brand and site to potential customers.
