backlinks

We all know just how important it is to get as many incoming links as possible. The top search engines love backlinks; and you don't need to be a rocket scientist to figure out that link popularity plays an important role in their ranking algorithms.

Does Google place varying levels of value on the types of links pointing to a site when it comes to ranking considerations? This is one of the most oft discussed topics on the subject of Google linking strategies. Will Google punish what it may perceive as too many links too quickly? Are relevant links the only ones given weight?

On the forums or by email I am often asked the following sort of question: "How many Backlinks do I need to get in order to have PR5?". The answer is simple and always the same one: "This question cannot be answered because the PR doesn't only depend on the number of backlinks, it also and above all depends on the PR of each of those links..." Or to put it differently, a page can have PR5 with a single backlink whereas another one can have 3,000 backlinks and PR5 too.

How do search engines evaluate relevancy when ranking search results? Do they concentrate on optimized content, or do they value contextual backlinks more? Do they place more importance for on page content (optimized web copy)? Or do they emphasize off page, anchored links pointing to the site in question?

What's the best way of finding all the existing links to your site? It's widely acknowledged that Google doesn't show all the links when you do a "link:www.yoursite.com" search. Dave Hawley said that Google confirmed to him that they only ever shows a sample of the links to a given site.

When a web page is accessed by a link from some other page, the address of the other page (the "referring page") is made available to the web server. We can pick that information up from logs or as the page is being displayed. For example, if we have Server Side Includes or php, we can pickup the referring page from an environment variable. Here's a snippet of Perl code that does that: $frompage=$ENV{HTTP_REFERER}; $thispage=$ENV{REQUEST_URI}; Yes, there's a missing R in HTTP_REFERER. Yes, that's wrong, but that's what the variable is so that's what you use.