What is external telephone line for fax?

Question

What is external telephone line for fax?

Answer 1

External means " outside " .  You need to explain more of what you are trying to do so you can get a better answer to your question, but is this what your trying to do ?

Are you trying to hook up a Fax Machine to a Telephone Line ?  If You are,  then one end of Telephone Cord goes in back of Fax Machine and the other end goes into the Wall Outlet of your Phone Jack .

Which are both " externals "  or  " outside " your machine .

Answer 2

Don't know what "external" term means.

But, often people will subscribe to a 2nd phone line for use with Fax.  That way sending/receiving Faxes won't interfere with regular telephone calls.