Cable vs Wire
Cable and wire are conductors used in electrical and communication fields. If you ask someone the difference between wire and cable, chances are that you will draw a blank. This is one of the most confusing questions in the electrical field. There must be solid difference between the two or else there would not have been two different terms for a single entity. Well, a wire is a single conductor while cable is a group of two or more conductors. It is this insulation around the conductors that classifies it as a cable or else it would be a wire. There are 4 types of wires and cables consisting of single conductor, multi conductor, coaxial and twisted pair.
Talking of wires, they can be either solid wire or stranded wires. Both these wires are commonly used for many electrical purposes. A single conductor, either bare or insulated by a protective colored sheath is called a solid wire. Offering low resistance, solid wires are perfect for use in higher frequencies. When many thin strands of wires are put together inside a covering, it is called a stranded wire. Stranded wire has a longer life because of flexibility and can be used for a longer period than a single conductor.
Cables are of different types such as twisted pair cable, coaxial cable, multi conductor cable and fiber optic cable. As the name implies, a multi conductor cable is made up of many conductors insulated from each other. It is used very commonly for control but never is signal applications.
When a pair of cable is twisted around each other, it is called a twisted pairs cable. This is the arrangement that is best suited for carrying signals. Twisted pairs cable was invented in 1880’s especially for use in telephone wiring. Interference is greatly reduced by twisting wires around each other. Both multi conductor and twisted pair cables are called balanced line configuration cables.
Coaxial cable is an example where signal on the two conductors is not same. As such it is called an unbalanced line. This leads to interference but the performance of this type of cable is more stable than twisted pair cable.
Fiber optics cable is of three types such as plastic fiber, multi-mode fiber, and single mode fiber. Among fire optics cables, plastic fiber is the largest. It is made of plastic and commonly used in sending audio signals. For sending data, multi mode fiber, made of glass is used. The thinnest of the three is single mode fiber. It is so thin that it can be seen with a microscope only but gives the best performance. However, it is very difficult to connect together.