Is Page Rank real?

A lot of times I see what appears to be "inflated" PRs.

That is a website that looks "weak" with very few backlinks... yet is PR5 or something.

Does a link from these site really count?

ALSO, i stick these into Ahrefs.com or Opensiteexplorer.com and it shows no authority.

And sometimes I put a website that's only PR2 or 3 but in Ahrefs.com or Opensiteexplorer.com it shows pretty decent authority.

Which do I page more attention to?

Take PR with a grain of salt. I generally just use it as an indication of the site's authority. Use PR with other tools such as Alexa rank to get a better picture of a site's background.

So just cuz a website has a PR6 doesn't mean it'll actually ass PR6 juice?

Very strange notation page rank. I have a domain that has been noted directly 3. It has nothing on it. I did not do any action by seo. It is only on same hosting with cPanel same domain with pr 2.