Input/Output (I/O)

Input/Output, commonly referred to as I/O, is a core concept in computing that describes the interaction between a computer system and the outside world. I/O encompasses both physical connections and digital communication between computers and peripheral devices. It is organized into categories of device-based and network-based I/O, with the former classifying devices like disk drives, keyboards, and mice, and the latter covering technologies such as Wi-Fi, Bluetooth, or modems.

In computing, commonly used I/O techniques involve the transfer of data from one source to another via physical media. This includes anything from USB connections to data storage on hard drives and flash drives, to wireless data networking using Wi-Fi or Bluetooth. In each case, the output from one system is sent to another, which then processes the data. This is done using different protocols, such as TCP/IP (Transmission Control Protocol/Internet Protocol).

I/O is also used to refer to how a computer interacts with the user, through a graphical user interface (GUI) or virtual reality technology. Typical examples of this include touchscreen devices, like smartphones or tablets, or holographic displays.

I/O is critical to modern computer systems and programs. Without it, machines would have no way to interact with data sources and the user, leading to ineffective computing experiences. It is, therefore, an important foundational concept of computing and information technology, and one that students of the subject must understand.