This may be Greek to you but I wanted to discuss sub-domains and sub-folders (sub-directories) and the differences between them.
A sub-domain is a completely separate domain (URL) sort of riding on the back of the main site like this: blog.website.com
A sub-folder is another platform that has been installed in the file system (FTP) of the website and may look like this: website.com/blog (or anything else after that slash that's NOT actually on the website) The slash indicates a folder or file that has been installed on the website itself, where the . (dot) indicates a completely different website.
Why would there be a difference?
We use sub-domains mainly for blogging purposes. If a website does not have a blogging platform (unlike Wordpress, Real Geeks, Etc..) we need to create one in order to maintain a revolving blogroll. For this reason, we will create a sub-domain like we have done for our client KeytotheBay.com The main site does not have a blog platform so we created a WP site with the domain blog.keytothebay.com The authority lies with the KeytotheBay but we actually have a completely different website here.
Sub-folders are when the host or website originator will install a blogging platform right into the file system of the website. It becomes part of the main website domain, but a separate file on the site itself, while the blog portion is off-site on a WordPress Platform.
If you remember when ActiveRain paired with Trulia and created the domain ActiveRain.Trulia.com This is an example of a sub-domain. We looked like we had the authority of Trulia but were still our own site.
Why use a sub-domain?
- Host a Blog
- Categorize Different Regions
- Organize Different Products
So what are the pros and cons of a sub-domain vs. a sub-folder?
Pros of a Sub-Domain:
A sub-domain is a good option when you don't have a blog platform on your site and you don't want to give up or relocate your current site.
It can be keyword heavy and can be used as a different marketing tool like for print flyers or mailers.
You build trust and authority when users and readers see the domain is the same. If they have trust in your domain, they should trust the sub-domains.
The more sub-domains the higher chance of appearing in search engines. (in theory)
Google is smart enough to see that both the sub-domain and the main site is tied into one website.
Pros of a Sub-Folder:
Trickle down effect works because you're building pages on the back of the main domain within the site files itself.
Far less work - you're only maintaining one site vs. many.
Cons of a Sub-Domain:
Each sub-domain is treated separately, separate Google juice, backlinks AND maintenance. You have to maintain a completely different website now even though it rides on the domain of the main site.
No trickle down effect so you have to market it as you would the main domain.
It needs to be hosted separately.
Takes longer to rank and index (maybe)
Needs it's own SSL certificate.
May look different than the main website, since it's a different platform altogether.
Cons of a Sub-Folder:
Getting the Google bots to crawl and index it correctly. This is why organizing sub-folders is so crucial.
You may not be able to have this if your website provider will not give access to a blogging platform. WIX and Website Box are like this. You do not have access to the files and therefore cannot install a blogging platform into it.
The whole idea is to use which ever works best for you. Have a Wordpress website? Don't bother! You have the site and blog altogether. But, if you don't and you'd like to have an off-site blog but you don't want to lose your main site, then find out if you can have a sub-folder attached to it. If not, then you have to create a sub-domain and have your own blogging site away from your main site, but to readers, it still looks like it's all one and the same.
Both SHOULD be indexed and ranked the same (according to Google). Google has also fixed gaming the system where you can't just have a ton of sub-domains to dominate the homepage. Google is smart enough to realize it's really all from the same website.
Bottom line: Find what works for you. If you have a WP site, no need to do anything. If you have a site that you love that doesn't have a blogging platform, ask if you can have your own blogging file (sub-folder) added, AKA Wordpress. If you can't, consider a sub-domain of your website domain and just start blogging over there. To readers, it will look like the same site, even if you can't get it to "look" exactly the same (because you're on a different site).
So How Can You Rank?
The same way any site ranks; authority and backlinks. Either one can create great links back and forth and the sub-domain can be used to create those backlinks even though they won't be high value to start off. The more information and the better you blog and promote, the quicker you can rank for not only the blog, but the main site you are consistently linking to.
Sub-folders tend to rank a little faster because you're riding on the backs of the existing website, therefore your main site may already have authority and so the sub-folder will carry some of the weight of the main site.
Use what works for you. Don't stress about it too much but do make sure you don't have a ton of domains out there all doing different things and none actually building awesome authority. Whatever you choose to do, do it well and you will be rewarded.
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