Backlinks from educational and government sites are the most valuable assets of a website because the .edu and .gov domains are not sold by any registrar on the internet.
These are not common sites which everyone can make. So, search engines like Google, Bing, Yahoo! and others value backlinks from .edu and .gov sites the most.
Sometimes, your site can rank at first page of Google with only 1 backlink from such a high authority site!
A redirect backlink, to my understanding, is a backlink someone has generously posted to go to your website, but is to an outdated part of your website. In an attempt to salvage the effectiveness of that backlink on your google ranking (or SEO), you make sure that backlink redirects to the content that it’s looking for, which you might have moved, or at the very least, goes to something that is otherwise relevant or important on your website.
Not sure how this would be considered black hat SEO, maybe I’m not understanding your question. Speaking of, I can’t think of anything really that would be considered black hat SEO, although I’m not too experienced in it. It’s my understanding that those types of activities (e.g. mass posting a link to your site on thousands of sites) may have helped you in the ancient history of the internet, but nowadays, these types of things only hurt your ranking, especially with Google.
The thing is I don’t know. It goes like this: (just an example)
http://www.fws.gov/pacific/script/exit.cfm?link=your link here
