The standard from of a number is the usual way or most common way to write the number. The numbers below are in standard form.
31
95
814
2
14
448
When the standard form of a number has at least four digits, commas are used to separate groups of 3 digits as shown below.
4,789
35,985
789,147
2,456,369
64,001,347
9,000,000,000
We use commas when the number has at least four digits in order to make the number easier to read when it is in standard form.
For example, it is easier to read 874,001,748,102 than it is to read 874001748102