Hibernation the summer months is aestivation. Often associated with low temperatures, the function of hibernation is to conserve energy when sufficient food is unavailable. To achieve this energy saving, an endothermic animal decreases its metabolic rate and thereby its body temperature. Hibernation may last days, weeks, or months depending on the species, ambient temperature, time of year, and the individual's body condition. Before entering hibernation, animals need to store enough energy to last through the duration of their dormant period, possibly as long as the entire winter. Larger species become hyperphagic, eating a large amount of food and storing the energy
Hibernation (computing) and hibernation: The machine can resume instantaneously, and its state, including open and unsaved files, survives a power outage. Hybrid sleep consumes as much power as sleep mode while hibernation powers down the computer. Early implementations of hibernation used the BIOS, but modern operating systems usually handle hibernation. Hibernation is defined as sleeping mode S4 in the ACPI specification. On Windows computers, hibernation is available only if all hardware and device drivers are ACPI and plug-and-play–compliant. Hibernation can be invoked from the Start menu or the command line. Windows 95 supports hibernation through hardware manufacturer-supplied drivers and only if compatible