Part I: Games & Gaming · Slot Machines & Electronic Gaming

Virtual Reel

Slot Technology

A software-based representation of a physical reel strip that contains more symbol positions than the physical reel it controls. The virtual reel map associates each RNG output number with a specific virtual stop, which is then mapped to a physical stop on the visible reel. This technology, enabled by Inge S. Telnaes’ 1984 patent, allows game designers to create symbol distributions with widely varying probabilities — including jackpot odds far exceeding the physical limitations of reel-based machines. Virtual reel mapping is the foundational technology that enabled modern slot machines to offer multi-million dollar jackpots while maintaining profitable hold percentages.

In practice

A physical reel may have 22 stops while its virtual reel has 64-128+ stops, with high-value symbols assigned to very few virtual positions. The player sees the physical reel stop but the outcome was determined by the much larger virtual reel.

One entry from the Casino Industry Glossary — 1,157 terms written for surveillance, compliance and operations professionals rather than for players. Definitions describe industry usage; where a term carries a regulatory meaning, verify against the instrument that governs your jurisdiction.