link up vs attach

link up and attach both are verbs.

Word	Noun	Adjective	Verb	Adverb
link up	No	No	Yes	No
attach	No	No	Yes	No

As verbs, attach is a hyponym of link up; that is, attach is a word with a more specific, narrower meaning than link up:

link up (verb)	attach (verb)
make a logical or causal connection	become attached
connect, fasten, or put together two or more pieces	cause to be attached
be or become joined or united or linked	be attached; be in contact with
	take temporary possession of as a security, by legal authority
	create social or emotional ties