Zero-sum vs Non-zero-sum

“A zero-sum game is a mathematical representation of a situation in which each participant’s gain (or loss) of utility is exactly balanced by the losses (or gains) of the utility of the other participant(s)…In contrast, non-zero-sum describes a situation in which the interacting parties’ aggregate gains and losses can be less than or more than zero.” (related: win-win — “A win–win strategy is a conflict resolution process that aims to accommodate all disputants.”)

Gabriel Weinberg's Mental Models I Find Repeatedly Useful