page_title: Glossary of computer hardware terms
section_title: W
hierarchical_section_title: Glossary of computer hardware terms / W
caption_attribution_description: This is a 'Sweex miniwebcam USB' with its casing removed. The top image shows it with lens in place - it is fully working in the upper photo - while the bottom image shows the CMOS image sensor without lens.
context_page_description: This glossary of computer hardware terms is a list of definitions of terms and concepts related to computer hardware, i.e. the physical and structural components of computers, architectural issues, and peripheral devices.
context_section_description: webcam
  A video camera that feeds its images in real time to a computer or computer network, often via USB, Ethernet, or Wi-Fi.
  write back cache
  A cache where store operations are buffered in cache lines, only reaching main memory when the entire cache line is evicted.
  write through cache
  A cache where store operations are immediately written to the underlying main memory.
  working set
  The set of data used by a processor during a certain time interval, which should ideally fit into a CPU cache for optimum performance.
caption: A webcam typically include a lens (shown at top), an image sensor (shown at bottom), and supporting circuitry
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