# Highest order bit
Abstractly, the highest order bit is the piece of information in a decision that, if different, would make the biggest change to what action you would take. It’s a useful frame when making an extremely multivariate decision — instead of trying to do some weird optimization, if you can identify the ‘highest order bit’ you can just focus on getting that right.
As a mental model, highest order bits are similar to [[Binding Constraint]]s.
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