What means a back door link. Please explain and I will give you credit

[Joseph-Green-SEO]

Some one is asking me to do a back door link to each other, what dose it mean?

[KaneJamison]

I do plenty of link building, but honestly, I'm not familiar with this term.

Based upon the fact that they're asking you to link to each other, I'm guessing that they want you to create a link to their site from an internal page on your site, and that they will do the same in return. If that's the case, it's a slightly better version of reciprocal linking, where you each have a page A linking to each others page A.

If the link posted by SEO 5 Team is what you're referring to, that's much more commonly called second tier link building, which is essentially building links to a page that in turn links to you or your client.

Whether or not this person's offer is worth it depends on the site you'd be linking to, and the site you'd be getting a link from. Most likely, it's not worth your time.

[CleverPhD]

Just some advice, I would not search for backdoor link on urban dictionary.  Nuff said.  Yosepr, read the link that SEO 5 Team posted and it explains it all.

Basically, you link to page on a site that then links to a page on the site you are "back door" linking to.  It is an indirect way to link to the other site as you link to a page that links to them (and then vice versa).

[Joseph-Green-SEO]

Thanks.

I do not understand.

Someone is asking me to do a backdoor link to each other; what dose it mean and what is it different from any other linking?

[SEO5Team]

Hi Yosepgr,

Backdoor linking is a way to build links to a site using content also constructed on the behalf of the client. This is usually found by creating value-adding content for sites already verified as relevant to your content. There are tools to help further build links to this content, such as AHrefs, SEO Moz, Ayima v2 and Majestic SEO; these tools find as many live pages as possible linking back to your client, so be sure to check them out, too.

An informative article from Alchemy Viral can be found here explaining more.