Subdomains. Anything I should know about them?

Don't want to hurt my normal site.

[Soze]

I am a huge film and book person, and I run a rather successful blog (not on films and books, but rather politcal blogging). My main domain is a pr6 and my domain.com/blog/ is a pr7.

My friend and I are thinking about creating a reviews.domain.com subdomain and designing a totally seperate site where me and my friend could review everything that we see and read. I was thinking that if I tossed some links up from my current site, we could start gathering an audience a little quicker than starting a totally new site.

Do you think this will throw up and flags or bring on any penalties if I do so? I don't really want to damage my own site in the process.

[tedster]

One subdomain, honestly created and regularly developed over time should not cause any problems. Yes, there is "subdomain spam" that Google struggles against but it involves a lot more than a single subdomain.

[wmuser]

I dont think it will cause a problem but dont "overlink" to it

[minnapple]

Today Google looks as subdomains at as unique entities.

Each subdomain for the most part stands on it own merits.

Linkage isn't associated between the main and sub like it used to be.

[wackybrit]

There may be a bit of a revolt on subdomains, to some extent. Look at what happened here:

<snip>

Billions of subdomains from a single site clogging up the index.

[edited by: lawman at 11:53 am (utc) on June 18, 2006]
[edit reason] No Outing Please [/edit]

[Quadrille]

I agree that an honest subdomain or two will not hurt you - any more than a few honest reciprocal links.

But neither will it do you any favors. As stated above, Google sees it as a new domain (ie www.domain.com + www.domain1.com), which means in ranking terms, it's a new site. If the connection is close enough for reviews.domain.com to work, then consider www.domain.com/reviews/ and concentrate your efforts on one site rather than divide - and be conquered ;)

Before subsomains become the spammer's latest fad, I divided a site into domain.com/folders into domain.com + sub.domain.com and sub2.domain.com. The main site was unaffected; sub1 did very well, thankyou, and sub2, a more specialist area, fell apart. I'd thought the topics were related, but different enough to justify subs - visitors didn't care either way - but SEs and directories did; each sub needed SEO independently (trebling the work) - and many quality directories will not list subdomains (pure snobbery, but there ya go!).

So, if it deserves its own site - give it its own domain, too. If it doesn't - folders are free :)

[Soze]

Today Google looks as subdomains at as unique entities.

Each subdomain for the most part stands on it own merits.

Linkage isn't associated between the main and sub like it used to be.

So how about what happened with expedia and it's spammy pharma subdomains. Surely Google is attributing something to a subdomain of a regular site. How else could a "new site" with only links from expedia (though it is a powerful site), outdo viagra's main page so easily?

[Quadrille]

So how about what happened with expedia and it's spammy pharma subdomains. Surely Google is attributing something to a subdomain of a regular site. How else could a "new site" with only links from expedia (though it is a powerful site), outdo viagra's main page so easily?

I'm not familiar with such subdomains, but any site created by a major 'authority' site will do well, - being a subdomain isn't the issue; froogle.google.com does well - but if google had placed the site at froogle.com, that would have done just as well.

For all practical purposes, Google treats subdomain.domain1.com exactly as it would treat domain2.com

[Rosalind]

Creating multiple subdomains, of itself, isn't a sign of spam. Lots of sites do it in order to give users their own profile, blog, or whatever.

But the way subdomains are treated has led to abuse, particularly in the past week. The recent incident seems to have led to a manual ban for one spammer, and a considerable number of would-be blackhats asking for scripts to create subdomains on the fly.

At the moment having multiple subdomains has an advantage over large websites that aren't split up into subdomains: they get better crawl depth. I wouldn't bet on this lasting past the next algorithm update, but you never know.