Refers to the number of bits that can be processed
or transmitted in parallel, or the number of bits used
for single element in a data format. The term is often
applied to the following:
microprocessor: indicates the width of the registers.
A 16-bit microprocessor can process data and memory
addresses that are represented by 16 bits.
bus : indicates the number of wires in the bus.
A 16-bit bus transmits 16 bits in parallel.
graphics device, such as a scanner or digital camera :
specifies the number of bits used to represent each pixel.
operating system: refers primarily to the number of
bits used to represent memory addresses. Windows 3.x
is a 16-bit operating system, whereas Windows 95 and
Windows NT are 32-bit operating systems.
expansion board: refers to how much data can be sent
to and from the card in parallel. 8-bit cards are
sometimes called half-size cards whereas 16-bit cards
are referred to as full-size cards.
source: https://www.webopedia.com/TERM/1/16_bit.html
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