A Short Glossary of Different Types of Wires Found in Your Home

The average home contains thousands of feet of wire running virtually everywhere. Every space that features an electric light, a power plug, a switch, or even any sort of built-in entertainment or communication infrastructure undoubtedly depends on some sort of wire or cable, and most of it is hidden out of sight behind drywall. Not only does this make electrical wiring safe and convenient, but it keeps our homes looking beautiful and mess-free (after all, nobody likes to stare at giant, disorganized piles of wire spilled everywhere).

However, many people don’t actually know what kinds of wires run through their walls and what each one does. Knowing more about the wire and cabling in your walls can help you better understand how your home works, what to expect should you need to service an electrical system, and what is possible with modern technology.

Here are some of the most common types of wire found in your walls, as well as a description of what each one does.

Romex

The name Romex is actually a brand name that is widely recognized as the standard for a certain type of wire known as “non-metallic sheathed cable.” Think of how the name Kleenex is often used to refer to facial tissue. This type of cable is widely regarded as the standard for electrical cabling because it seamlessly and easily combines all three wire lines needed to run a safe, modern electrical circuit into one easier-to-handle cable. If you remove the outer coating, you’ll find that Romex wire is actually three different wires combined into one: a black “hot” wire, a white “neutral” wire, and an unshielded or green “ground” wire. By running a single instance of this cable into a junction box, you will have all three of the wires that you need, making installation a breeze. Plus, with the added protection of additional shielding, these cables are safer as well.

Coaxial

A coaxial cable is typically a round, fairly rigid type of cable that’s approximately a quarter-inch thick. The connector on the end of these cables is typically a small, single brass pin with a freely rotating threaded nut on the end designed to establish a secure connection. You will typically use one of these cables for two things: your television box or your internet. This is because coaxial cables are typically used as a type of data transfer wire. Due to their ability to transmit data over longer distances with very little loss, these cables are still one of the “gold standards” when it comes to wiring. However, these are not the only applications for coaxial cabling—because they are so good at transmitting fairly large data signals over longer distances, these cables are popular for home security systems, particularly video surveillance.

CAT5/CAT6

Typically thought of as the “phone” cable or the “internet” cable, CAT5 or CAT6 cable are another common way of transmitting data over longer distances with minimal loss. Unlike coaxial cables, CAT5 and CAT6 cables are composite cables that are actually several different wires all combined into one. This has a number of benefits, including a unique one that coaxial cable can’t match: coaxial cables can’t transmit power. CAT5 and CAT6 cables can carry a small DC current from point to point over positive and negative wires that run through the line.

Stereo

Stereo wiring typically consists of two different wires running to and from each speaker. Speakers are typically driven by an analog signal, and that means they’re actually not all that unlike a simple DC electrical circuit requiring a positive line and a negative line. For that reason, stereo cable is typically two different individually-shielded wires with the two sides attached to one another to make it easier to work with. While these lines are sometimes color-coded, stereo wiring is often either black or clear, and the only differentiating factor between the two lines is a simple white or red line that runs through one of the two sides to indicate which side is which.

For home theater enthusiasts, music junkies, or those looking to be able to enjoy some tunes while using their patio or the pool, stereo wire will undoubtedly be something you will want to run in your home. However, because speakers are often best when placed all around you, you might have several long lengths of wire running through your home. For this reason, stereo wire installation is growing rapidly in popularity, particularly for those looking for a cleaner and more permanent wiring solution.

Display Wiring

Finally, display wiring is a thicker and typically shorter type of cable designed to work with a modern display protocol. Perhaps the most common modern display wire type is an HDMI cable: a simple, easy-to-use, and yet immensely powerful protocol for carrying high-quality video from point to point. HDMI cables are generally quite thick, typically because they are also larger composite cables that contain several different strands of wire rolled into one. However, unlike coaxial and CAT5/6 cables, these cables are generally not designed for long distances. This is why you often won’t find an HDMI cable longer than around 10 to 15 feet.

Because HDMI cables, display port cables, and other common cables used to connect televisions or projectors to streaming boxes, Blu Ray players, and other entertainment equipment can create a visual mess that is difficult to control, many people are choosing to run these wires inside their walls for a cleaner look with less mess and clutter.