Board Thread:General Discussion/@comment-9336282-20170907000354/@comment-32354545-20170907203535

"Project:" is just for creating wikilinks, which in wikitext (source code) is represented as  or what have you; this source code is obscured if you use the visual editor, but Project: still works just as well as the full project namespace name.

To move a page to "Project:Foo" you can either pair "Project:Foo" or "Some Assembly Required Wiki:Foo" with the (main) namespace option, or "Foo" with the "Some Assembly Required" namespace in the drop-down.