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Mustafa Fink
41 PointsWhy Don't you put inverted commas around 4 in var number = 4;
In the nextstep inverted commas were around hello but not around 4 why?
2 Answers
![Bonnie McBride](https://uploads.teamtreehouse.com/production/profile-photos/11663700/micro_joly.jpg)
Bonnie McBride
1,755 PointsData types. Anything in between the inverted commas is a 'string'; a text data type. If you type the number 4 not in inverted commas, then it is a number data type, and can be used to do calculations. You cannot do calculations with a text data type.
![Steven Parker](https://uploads.teamtreehouse.com/production/profile-photos/969492/micro_tool_chess_set_2.jpg)
Steven Parker
230,688 Pointsi believe what you are referring to as "inverted commas" is typically called "quote marks" or just "quotes".
And quotes are used around strings, but not around numbers. You can do math (like "number + 1
") only on numbers.