sub-domains and SEO

[guya]

I've recently changed my web host and it seems the new one allows sub-domains; ie. shop.mywebpage.com, information.mywebpage.com...

My question is, does a relevant sub-domain name help in SEO? My domain name is unfortunately not the same as the keyword I am optimizing for, though I have a PR of 5 and am on page 1 (10th) of Google when searching for the relevant keyword - we have quite a lot of relevant backlinks fortunately which has helped in ranking in Google.

I am thinking of creating a sub-domain like relevantkeyword.mydomain.com with the hope that this will raise my rankings even further with Google? Does anyone have experience with sub-domains? I have the feeling that relevantkeyword.mydomain.com will get given a PR of 0 after Google's next major update, rather than automatically get assigned a PR of 5 with the main domain.

Any comments anyone?

[nickc]

Google treats subdomains as completely different sites and won't inherit PR from another site (unless it redirects).

Nick

[fathom]

Originally Posted by guya

I've recently changed my web host and it seems the new one allows sub-domains; ie. shop.mywebpage.com, information.mywebpage.com...

My question is, does a relevant sub-domain name help in SEO? My domain name is unfortunately not the same as the keyword I am optimizing for, though I have a PR of 5 and am on page 1 (10th) of Google when searching for the relevant keyword - we have quite a lot of relevant backlinks fortunately which has helped in ranking in Google.

Not really. While the appearance seems to induce "more backlinks" per each domain (subdomain) the internal site architecture in dramatically affected.

The overall occurrance: you dramatically increase each subdomain's "hub score" and dramatically reduce each subdomain's authorative score + dramaticaaly decrease available page content of your primary website, by encircling it with a bunch of smaller "less expert or authorative" sites.

Unless you have a ongoing, rapid increase of content in each subdomain I highly recommend you drop the subdomain... they are useless in site architecture that change little over time.

Best use of subdomains:

1. a forum (dramatic increase in repository content over time)

2. a blog (same as #1)

3. a directory (same as #1)

4. news/articles (possibly same as #1)

5. RSS feeds

The jest: you need a large and growing repository of content to offset the increased hub score.