System by which votes are recorded in a voting location by means of marks made in voting targets designated on one or both sides of a ballot card or series of cards. An optical scan system reads and tabulates ballots, usually paper ballots, by scanning the ballot and interpreting the contents.
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System by which votes are recorded in a voting location by means of marks made in voting targets designated on one or both sides of a ballot card or series of cards. An optical scan system reads and tabulates ballots, usually paper ballots, by scanning the ballot and interpreting the contents.
Cite this term
Election Security Glossary. (2026). Precinct Count Optical Scan System (pco). In Election Security Glossary. Retrieved August 13, 2026, from https://electionsecurityglossary.com/glossary/precinct-count-optical-scan-system-pco
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