There are several link building strategies that are constantly repeated on the web; deep linking somehow isn't one of them. I often wondered why that is, but after a few years working in the SEO industry it is fairly easy to realize why. It is because link building and SEO is mostly promoted by newcomers that just repeat the first things they read on a blog or article no matter how old it is. So you have a bunch of old strategies being repeated over and over again and people tend to get lost in that sea of information and fail to find the quality behind the words they read.
So before we get to the deep linking and the importance of deep linking in your link building strategy, let us name and score the most common link building methods there are:
Blog Commenting - this is one of the most used link building methods, the benefits are that you can create a massive number of links using this method, but the flaw is that search engines don't value blog comment links as much and most of them are no follow.
Forum Posting - This is the same as blog comments, you can build a lot, but the results are not that great, and if you use it too much you can get banned from a forum as you will be considered as a spammer.
Article Marketing - This is the second level of link building along with PR. These are great links and as they get older they can become quite powerful. The flaw is that you will have to wait a long time before you see the best of them, but if used with quality articles and proper anchor text linking they will give you an immediate boost.
Link Bait - This is a passive way to build links, but it is the best in the world when it comes to link building. The benefits are great, but on the other hand the flaw is that you don't control the links, where they are coming from and what anchor text they have, so they are not perfect.
Asking for Links - This is the best linking strategy in my book. Yes it requires time, but instead of focusing on the number of links we are focusing on the quality. We find a website we want a link from, we find the page we want the link from and we choose the anchor text we want to be used as a link. We get the best of the best; the hard part is actually getting the link. The most important thing to do is think why that website would want to link to you, if you present it in a good and interesting manner most of the web owners will gladly link to your website.
This got a bit longer than we expected, but in order to properly use deep linking you need to know the methods and link building strategies to use in your link building campaigns. So let's keep the rest simple, why you need deep links?
There is no way that you can optimize your entire website for all the keywords you want to rank for, so that is why you have categories and pages on your website. Those pages are more relevant for some keywords than your homepage, which is the first reason why we use deep linking in our link building strategy.
The second reason and maybe even more important than the relevancy of the link is building the authority of your entire website and not just one page. The more deep links you have the easier for Google is to consider that you have quality content on your entire website and not just your homepage.
Overall deep linking is necessary if you wish to achieve a good rank for certain keywords and increase your authority, plus the visitors that come to your website using those links will land on a relevant page, which is a great bonus for you.
Remember to build your links as naturally as you can, no spamming and no massive link building attempts, go for those quality links that can replace 1,000 of blog comments and forum posts, they are worth it. And be sure to mix it up with various anchor texts and deep linked pages, make a 1 to 5 ration of all the links going to your homepage and to your deep pages. With deep linking you simply can't go wrong in your SEO strategy.