Hook-up wire is an insulated single conductor. It is often used for short point-to-point connections within components, racks, electric guitars, etc. A little trick I have used for years is to twist two different colors together to make unshielded twisted-pair (UTP) cable. Just play out a few feet and fasten the ends in a vice. Fasten the other ends in a battery-powered drill and twist as tightly as you please.
I recently discovered a really nice hook-up wire designed for use in electric guitars.
From the website: 22 AWG unshielded single conductor wire is tinned and stranded, with a white celanese wrap and waxed braided cotton outer insulation. The cloth insulation simply pushes back to expose the center conductor wire.
Since it is both stranded and tinned, two strands can be combined to form an especially tight twist that doesn’t untwist itself due to memory effect. For soldering to connectors, just push back the insulation – no stripping required. pb
Photo Below – The twisted-pair is tight and retains its shape, right up to the connection point.