http://en.wikipedia.org/wiki/Twisted_pair

The twisted pairs and the shielding are clearly visible

quoting original Summary:

Created by {{user|Mozzerati}} and made available under the GFDL or CC-SA licenses.

This is a photograph of a [[:wikibooks:en:foiled twisted pair|]] cable dissected.  From the outside (on the right of the photo) to the inside are the different layers of the cable.  The layers are as follows:

* plastic outer sheath, 
* ground, or drain wire (always in contact with the shielding), usually terminated to ground on one end only.
* foil shielding
* the plastic inner plastic cover
* the four pairs of two wires
** insulation on each wire
** the single core conductor