What Is a Dashcam?

Couple driving car adjusting dashboard camera

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Unlike most of the tech and gadgets you typically find in cars, dashcams aren’t designed to provide entertainment (or infotainment), offer any sort of comfort or convenience, or make it safer to drive. These devices tend to be small and compact, offer very little in the way of frills, and have one laser-focused purpose: to record everything that goes on in or around your vehicle on the off chance that something might go horribly awry while you’re on the road.

What Are Dashcams?

Dashcams are small video cameras that are typically installed either on the dashboard of a car, hence the name, although they can also be attached to the windshield or placed elsewhere. Virtually any portable camera or recording device can be used as a dashcam, but purpose-built devices typically:

  • Run on 12V DC.
  • Feature “always on” recording.
  • Automatically overwrite old data as new data is recorded.

Other features are often available, but this core set more or less defines the dashcam as a device. The ability to run on 12V DC means that the device can be hard-wired into a vehicle’s electrical system, 'always on' recording means that the device will automatically start to record whenever the vehicle is driven, and the ability to overwrite old data means that the driver never has to fiddle with old, unneeded video files.

How Do Dashcams Work?

Purpose-built dashcams are relatively simple. When they are installed, they are wired directly into the vehicle’s 12V electrical system. The power will typically be taken from a source that is only hot when the ignition is in the accessory or run position, which is due to the fact that dashcams are designed to constantly record whenever they are on, and they’re usually also designed to be on whenever they are supplied with power.

If a dashcam is intended for use as a security device when the vehicle isn’t actually in use, then it may be wired into a circuit that is always hot, or it may be powered by an internal battery or external second car battery to avoid draining the vehicle’s battery.

In either case, dashcams are designed to constantly record video data to removable storage media like an SD card, flash drive, or an internal solid-state storage device. When the storage device fills up, the camera will automatically overwrite the oldest video files. This design is meant to provide a sort of “set and forget” situation, where you can hook up a dashboard camera and then essentially leave it alone until you need it.

Are Dashcams Legal?

Dashcam legality is a complicated subject, so it’s always a good idea to check into the specific laws and regulations in your jurisdiction before installing one. They are illegal in some countries, legal in others, and video from dashcams can actually be used in court in many cases.

In addition to whether or not dash cameras are specifically legal or illegal in your area, it’s also important to consider privacy concerns. Although dashcams may not be specifically illegal in your jurisdiction, using one ​may break privacy laws, which makes it even more important to do your homework before you install one.

Dashboard Camera Alternatives

Although purpose-built dashcams are the most convenient, reliable devices for this particular type of usage, just about any small, compact recording device can function as a dashboard camera. Battery-operated hidden surveillance cameras are particularly useful, although handheld video cameras and even smartphones can also be used as makeshift dashcams.

The main disadvantage of using a dashboard camera alternative is that you have to turn them on and off manually and deal with potential storage issues. However, there are actually smartphone dash cam apps that can turn your iPhone or Android into a serviceable dashcam with the push of a button.