BIOS (Basic Input/Output System)

On PC systems, a set of routines that tests the hardware (e.g.,

disk drives, keyboard, and monitor) at startup, starts the operating system (OS), and supports the transfer of data between hardware devices at startup. Until the early 1990s, BIOS was stored in firmware , i.e., read-only memory (ROM). In contemporary computers, BIOS is written to erasable programmable read-only memory (EPROM) or flash memory to facilitate updates.

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• header suppression
• headroom
• Hearing Carry Over (HCO)
• heavy carrier
• heavy metal
• HEC (Header Error Control)
• Hellenologophobia
• henry (H)
• Hertz, Heinrich Rudolf (1857–1894)
• Hertz (Hz)
• Hexadecimal
• hexadecimal notation (hex)
• hexadecimal notation (hex)
• hex (hexadecimal notation)
• HFC (Hybrid Fiber/Coax)
• HF (High Frequency)
• HF (High Frequency)
• high bit-rate digital subscriber line (HDSL)
• high capacity voice (HCV)
• high-cost area
• high definition television (HDTV)
• high density bipolar order 3 (HDB3)
• high frequency (HF)
• High-Level Data Link Control (HDLC)
• high-order mode