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  "body": "\n## Example\n\nLet $\\mathbb{N} = \\{0, 1, 2, \\dots\\}$ be the [[natural numbers|0MWKJ44V5A]] with addition.\nAddition is associative, and $0$ is an identity element.\nThe element $1$ has no [[inverse|0BRHKKP333]], because $1 + m \\ge 1$ for each $m \\in \\mathbb{N}$, so $1 + m \\ne 0$.\nThus $(\\mathbb{N}, +)$ is not a group. It is a commutative monoid.\n\n## Remarks\n\nIf we add the negative integers, we get the group $(\\mathbb{Z}, +)$.\n",
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