A comma is a punctuation mark used show a pause or a separation. ( , )
In a very large number, we put a comma after every three places. The first three places of a number are still 100’s. Once we get a fourth place column in a number, we have reached the thousands.
999 – nine hundred ninety nine
1,000 – one thousand
10,000 – ten thousand
100,000 – one hundred thousand
The comma in a number helps us to read the number easily. Look at these two ways to write one million:
1,000,000 or 1000000
There are six zeroes in each number, but it is much easier to count the zeroes when commas are placed after every three zeroes.
Be sure to use a comma when writing any number longer than three place values.
A comma is also used to separate numbers within a written date.
Today is August 2, 2021. We use a comma to separate the date, August 2, from the year 2021.
If we eliminate the comma, the date looks like this: August 22021. We can all agree that a comma makes the date easier to read.
Remember to use a comma as a separator after each three place columns in a large number. Also use a comma when writing a date – between the day and the year.