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  "body": "\n## Summary\n\nA projection operation on a set $A$ is an operation $A^n \\to A$ that returns one fixed argument and ignores the others.\nThe projections are the operations given by single variables, so they are the simplest term operations of any algebra.\nEvery [[clone|PTKR703G6A]] contains all projections, and the set of all projections is the smallest clone on $A$.\n\n## Explanations\n\n### L1 human\n\nThe projection $\\pi^3_2$ takes three inputs and hands back the second one.\nFor example, $\\pi^3_2(5, 7, 9) = 7$.\nSuch an operation does no real computation; it only selects a position.\nProjections matter because composing operations needs a way to feed the same variable into several places, and projections do exactly this bookkeeping.\n",
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