Spiders are simple little animals and the theory that guides the way search engines are built admit of few special cases, so generally speaking, a link is a link is a link. Let’s consider some cases.

The most often question is what happens for the target="_blank" case. This is very common so it would have staggering consequences if it did not act as a "normal" link. Moreover, treating it differently is theoretically unsound, as linking into a new window is not conceptually different, in terms of citation considerations, than linking in the current window.

The question of the use of style classes and DOM ids also comes up. I am certain that these are simply ignored by all search spiders, but that is a subject for another day (why spiders are so dumb).

BTW, OptiLink and OptiSpider both treat all of these links the same. The only exception is the rel="nofollow" attribute (Google’s simplified approach to Dynamic Linking) which is optionally processed by both programs so that our computation of Link Reputation will follow what Google does.

When most webmasters talk about links, they almost always mean "navigation". There are several ways to connect your pages together so that humans can get from one to the next.

By contrast, there is precisely one way for spiders to get from one page to another and that is the HTML <A> tag. To look at a page in your browser, you will often be unable to tell what navigation is actually spiderable links. That’s one of the primary uses of OptiSpider.

OptiSpider, like the search engines, is only able to follow <A> tags — all other kinds of navigation, like Javascript, and form buttons as two examples, are completely invisible to OptiSpider.

So, if you are uncertain if your navigation is spiderable or not, just run OptiSpider and see which links are found and which are not.

First, let’s define terms.

Dynamic content generally means that pages are generated by some chunk of software by reading data from a database. This is a common design pattern for big catalog style websites.

But no matter how the content gets generated, it still ends up being just plain-ol’ HTML by the time it leaves your web server. What the browsers and search engine spiders see is no more nor less HTML than so-called "static" pages. So the content itself is certainly not a problem — the URLs might be.

To generate the right output, a catalog style site will typically use one or more parameters in the query string. For example, /product.jsp?model=12&color=green&style=7.

Historically, search engines have not liked these complex URLs because they will routinely lead to a (nearly) never-ending sequence of pages. A "plain" URL — one without a query string — tended to have an advantage over complex URLs.

This is not as much of a problem today as it once was, but it is still better to avoid complex URLs. To do so requires the use of a URL rewriting engine like Apache’s mod_rewrite module so it is fairly technical, but once done, a "dynamic" website can be made to look entirely "static".