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  "body": "\n## Summary\n\nA semi-local ring is a [[commutative ring|0310REJJY8]] with only finitely many [[maximal ideals|0PV74TR5FP]].\nIt generalizes a [[local ring|MZ02BKPHJA]], which has exactly one.\nSemi-local rings arise when one localizes at the complement of a finite union of prime ideals.\nThey also appear in the study of integral extensions of local rings.\n\n## Explanations\n\n### L1 human\n\nA local ring looks at one point; a semi-local ring looks at finitely many points at once.\nFor example, the fractions $a/b$ with $b$ prime to both $2$ and $3$ form a ring in which only the primes $2$ and $3$ remain non-invertible.\nThis ring has exactly two maximal ideals, generated by $2$ and by $3$.\nThe [[definition|Q256RTTNTN]] gives the condition.\n",
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