1 in Roman numerals, how to write?

1 = I
0 = ? ... 2 = ?

In Roman numerals online converter

Latest conversions of numbers to Roman numerals

1 = I Jul 18 06:51 UTC (GMT)
1,956 = MCMLVI Jul 18 06:51 UTC (GMT)
600,041 = (D)(C)XLI Jul 18 06:51 UTC (GMT)
2,006 = MMVI Jul 18 06:51 UTC (GMT)
8 = VIII Jul 18 06:51 UTC (GMT)
29 = XXIX Jul 18 06:51 UTC (GMT)
13 = XIII Jul 18 06:51 UTC (GMT)
5 = V Jul 18 06:51 UTC (GMT)
111,553 = (C)(X)MDLIII Jul 18 06:51 UTC (GMT)
86 = LXXXVI Jul 18 06:51 UTC (GMT)
6 = VI Jul 18 06:51 UTC (GMT)
15 = XV Jul 18 06:51 UTC (GMT)
20 = XX Jul 18 06:51 UTC (GMT)
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Roman numerals reading rules, summary: