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  "body": "\n## Summary\n\nThe order of a [[finite projective plane|2HWB7P1DZN]] is the number $n$ such that every line has $n + 1$ points.\nIt determines all the basic counts: each point is on $n + 1$ lines, and there are $n^2 + n + 1$ points and as many lines.\nThe plane $PG(2, q)$ over the field with $q$ elements has order $q$, and which other orders occur is a central open question of finite geometry.\n\n## Explanations\n\n### L1 human\n\nIn a finite projective plane all lines have the same size, so one number describes the size of the whole plane.\nBy convention it is one less than the number of points on a line.\nThe [[Fano plane|QQ8GW1ASZM]] has three points on each line, so its order is $2$.\nThe minus one makes the order of the plane over a field with $q$ elements equal to $q$.\n",
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