Driver

What is a Driver in a Computer?

A driver is a type of program used by the computer to communicate with a physical part installed in the computer. More specifically, it's software used by the operating system (Windows, Linux, etc.) to use a piece of hardware. Without an appropriate driver, the computer can't make use of a device at all.

Note: a "driver" with an "r" isn't the same thing as a "drive" without an "r."

When a device is connected to the computer, it sends some electrical signals to the CPU, and the CPU sends some electrical signals back to it. The program responsible for understanding what the signals that come from the device mean, and responsible for responding to them in a way that the device understands, is the driver.

In general, a computer can't use devices without its driver since it can't even know what kind of device it would be. For example, if the device is a mass storage device, where your files would be saved, sending the wrong signals could make the device erase all of its data and then you would lose all your files.

Nowadays the typical device has at least a bare minimum of support from the operating system without even installing any drivers. That's because most devices work similarly, so they all provide a common "generic" interface. For example, if your mouse and keyboard are connected via USB port, normally you would need a driver for them, but every typical mouse and keyboard works the exact same way, so instead of requiring custom drivers just to do the bare minimum, the devices will tell the computer in a standard way the type of device they are, and the computer will assign them a generic driver until a specific driver for them is installed.

Generic drivers can't make use of specialized functions that some devices have. For example, there are countless graphics cards, and what each one of them supports varies from the other. If you didn't have a driver, you wouldn't see anything on your screen even if the monitor was plugged because the CPU was unable to communicate with the GPU. This doesn't happen nowadays. They will at least display something on the screen. But if you have an Nvidia graphics card and you want to do something with its CUDA cores, you need the Nvidia driver for that graphics card.

Personally, I won't tell you to keep your drivers always updated. Every update can fix bugs, but they can also introduce new bugs. If it isn't broken, why fix it? However, if you plan to contact customer support about your device not working, you must make sure you have at least installed the latest drivers because your issue could have been resolved in the latest update already.

It's worth noting that drivers are widely supported on Windows, but not on less popular operating systems. A driver is a program created by the device's manufacturer. Most people have Windows installed on their PCs, very few have Linux, and an insignificant number have BSD. Consequently, a manufacturer WILL create drivers for Windows, probably won't create them for Linux, and there is a chance they have never even heard about BSD. See [How to Install Nvidia Drivers in Linux Mint] for an example.