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  "body": "\n## Summary\n\nTerm evaluation computes the value of a [[term|6D3WA7N2W4]] in an algebra once each variable has been given a value.\nThe value is defined by recursion on the term.\nVariables take their assigned values, and a function symbol applied to subterms is computed with the matching operation of the algebra.\nIt is the bridge between syntax and algebra: identities, term operations and the free algebras of a variety are all defined through it.\n\n## Explanations\n\n### L1 human\n\nA term such as $x \\cdot (y + 1)$ is only a formula on paper.\nTo evaluate it in the ring of integers, choose numbers for the variables, say $x = 3$ and $y = 4$.\nThen compute from the inside out: $y + 1 = 5$, and $x \\cdot 5 = 15$.\nThe same term evaluated in the ring $\\Z/7\\Z$ with the same choices gives $1$, so the value depends on the algebra as well as on the assignment.\n",
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