What is the advantage of using sub domains instead of pages on the root domain?

[designquotes]

Have a look at this example

http://bannerad.designcrowd.com/

For each category of design, they have a landing page on the sub domain.

Wouldn't it be better to have them as part of the same domain?

What is the strategy behind using sub domains?

[ThompsonPaul]

Hey designquotes - It's been a while since you posted this question. If you got the answers you needed, could you mark as  "Good Answer" whichever answers you found most helpful and mark the overall question as answered? This will help other users who may come across the question in the future.

Thanks!

Paul

[Andy.Drinkwater]

As Paul said, there is a lot more effort required to try and SEO each sub-domain as Google will see each as a separate entity.

However, there are times when a subdomain might be the preferred option - Just had a quick glance and can't see any reason why they would have chosen this route.

Andy

[ThompsonPaul]

Unless there's a tactical reason for needing separate subdomains which isn't apparent to the visitor, IMO this is a strategic error to be running all of these categories as subdomains.

They are requiring far more effort of themselves by having to work to rank each subdomain separately instead of taking advantage of the aggregation of authority that occurs with sub-folders and not with subdomains.

Paul