Reset button

In electronics and technology, a reset button is a button that can reset a device. On video game consoles, the reset button restarts the game, losing the player's unsaved progress. On personal computers, the reset button clears the memory and reboots the machine forcibly. Reset buttons are found on circuit breakers to reset the circuit. This button can cause data corruption so this button often doesn't exist on many machines. Usually, in computers and other electronic devices, it is present as a small button, possibly recessed into the case or only accessible by a pin or similar thin object, to prevent it being pressed accidentally .

The reset button could be an actual button or concept. The reset button would typically kick off a soft boot, instructing the computer to go through the process of shutting down, which would clear memory and reset devices to their initialized state. Contrary to the 'Power Button', which would simply remove power immediately.

Pressing the reset button would be preferable to the power button, which could potentially leave a device in the middle of some operation and subject to defect. In most commodity hardware, the consumer would expect the device to be resilient enough to 'reset' when power was restored.

Depending on the architecture, the reset button might have different effects. On PCs, usually it is connected to the motherboard, and when pressed it sends a reset signal to all peripherals.

Many newer computers have no separate button for resetting the computer; it is integrated with the power button. On most newer operating systems, the user can customize what happens when they press the power button. For example they may set it to 'Do nothing', 'restart', 'shutdown', or 'stand by'. This is only for pressing the button once; on most computers the power button can remove power immediately if held down for a few seconds. When the OS hangs, the reset button is no longer "integrated with the power button".

Many early microcomputers sported a reset button or key, such as the Apple II, TRS-80, and Atari 8-bit. Commodore did not include one on their computers until the CBM-II line.

The original IBM PC had no hardware reset button and IBM did not include one on any of their personal computers until the early 1990s, however many clones began sporting them early on. All PC compatibles can be rebooted by pressing Ctrl+Alt+Del, which triggers the BIOS startup routines and re-initializes and reboots the computer, but does not invoke the Power On Start Up Test (POST) or clear memory. Hardware reset buttons on PCs work by causing a momentary power interruption to the CPU, which resets it and causes the computer to reboot. Unlike Ctrl+Alt+Del, pressing the reset button causes the BIOS to perform the POST check. By the early 2000s, reset buttons had largely disappeared from PCs although the connector for them is still present on motherboards.

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