standby

Standby is a term for a state of readiness in which a device, system, or service remains in a low-activity mode but can be activated quickly. It is used across consumer electronics, transportation, and industrial contexts to balance responsiveness with energy use.

In consumer electronics, devices enter standby (or sleep) to enable fast wake-up while drawing relatively little power. Examples include televisions, set-top boxes, and computer peripherals that remain detectable by remote controls or networks when not actively used.

Standby power, sometimes called vampire power, describes energy consumed by devices while in standby. Although individual consumption is small, it adds up across households and appliances. Regulatory standards in many regions aim to limit standby power to roughly 0.5 to 1 watt per device.

Within computing, standby commonly refers to sleep or suspend modes. Suspend-to-RAM preserves session data in memory for quick wake, while suspend-to-disk saves data to storage. Both reduce active power but differ in wake time and persistence; hibernation is often separate from standby.

In travel and aviation, standby describes a passenger status where seats are offered if no confirmed ticket holders are available. Standby travel can be time-dependent and is subject to space and airline rules.

Standby power systems include standby generators and uninterruptible power supplies that start automatically after a power outage. They provide temporary or supplemental power until primary sources return or a permanent backup is installed.