The basic design may still be around, but if you compare the original with one that is used today on modern devices, you will find it divided into may more bands.<p>This because originally you had mono. Meaning you only needed two wires.<p>Then came stereo, but you could get away with using three wires.<p>So with the plug end being designated ground, they divided the upper band in two.<p>then comes phones and the idea of putting a remote on the headphones wire. &quot;Simple&quot;, divide the bands again giving a total of 4.<p>Thus when you plug it in, you have ground down at the bottom, and then some arbitrary divide of left, right, and remote.