Subdomain for SEO

Hey -

I'm turning here because I'm finding conflicting information. What's everyone's opinion/experience with using subdomains and how that effects SEO?

For example, am I hurting my brand if I'm using blog[dot]website[dot]com as opposed to website[dot]com/blog ?

Does it make a difference if blog[dot]website[dot]com is really our only main content source. So, landing pages, blogs, etc are all on the subdomain as opposed to the main domain?