What is the best for SE optimisation?
woops i thought you were a spammer. too bad you can’t unreport something sorry >.> anyway they are much of the same as far as search engines are concerned. doesn’t really matter if you use a sub-domain or a sub-directory both are acceptable. although for your own piece of mind (and tidiness of your account) you may want to use sub-domains for various projects at least thats what i would do.
“Subdomain vs Subfolder” for SEO is actually a very hotly debated topic on the internet. Google it and you can read for days. You can even find google officially contradicting itself.
One side of the debate suggests that subfolders are better to ensure that all of a sites contents count together for the search rankings. The other side of the debate says that google no longer treats blog.example.com and forum.example.com as two separate sites. Folks in the middle throw in some “facts” suggesting “popular” “big” sites like homedepot.com or walmart.com are treated differently than Joe’s blog and forum, and there may be a traffic threshold. Still others, suggest it’s how the sites are configured within google’s webmaster tools and how well they link each other as to whether two subdomains are related. Still others proclaim 2 subdomains will be treated as a separate site unless the google bot finds a “site map” tying them together.
The jury appears to be out, but if SEO is what’s important my choice would be the subfolder format. If I were just picking what I like I would go for subdomains.
I will use subfolder then
Just to add a little more fuel to the fire, Google recommends subdomains here, although it’s not specifically about SEO. I like the reasons though, which is why I prefer subdomains. I think they look cleaner and it’s less typing.