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JavaScript JavaScript Basics (Retired) Working With Numbers Numbers

Posted by Adam Castillo
Adam Castillo
7,585 Points

Do you ever have to declare a datatype in JavaScript like you have to in Java?

Does the browser automatically recognize data types?

6 Answers

Stan Zapalikov
Stan Zapalikov
1,915 Points

No, JavaScript is a weakly typed language.

Adam Castillo
Adam Castillo
7,585 Points
Adam Castillo
Adam Castillo
7,585 Points

Ok, thanks Stan.

Landon Sanders
Landon Sanders
1,262 Points
Landon Sanders
Landon Sanders
1,262 Points

No, Javascript is not strongly typed.

virus200
virus200
6,583 Points
virus200
virus200
6,583 Points

This was one of the first things I noticed starting the JS section since I have done some minor Java before. I was surprised you don't have to declare datatypes.

tkati
tkati
4,703 Points
tkati
tkati
4,703 Points

Some side notes: Being strongly typed and weakly type I'm pretty sure doesn't have to do with declaration of type. It has more to do if it can be changed. Dynamic vs static typed I think has to do more with when it can be changed or takes effect (compiler or run time). Not declaring a type doesn't mean it doesn't have a type. you'll still use typeof and === . == and === are both used in javascript, but the === also checks the type in addition to the value.

harman singh
harman singh
2,466 Points
harman singh
harman singh
2,466 Points

JAVA SCRIPT JUST SHARED A SAME NAME AS JAVA BUT IN JAVA DATATYPES ARE DECLARED BECAUSE JAVA IS OBJECT ORIENTED AND THE CONCEPT BEHIND OOPS IS ENCAPSULATION AND INHERITANCE SO EACH VARIABLE HAS A DATA TYPE OF CLASS OR BELONGS TO CLASS . BUT IN JAVA SCRIPT ITS IS MORE WEB BASED LANGUAGE SO HERE DATATYPE IS NO NEED AND BROWSER HAS IN BUILT COMPILER TO COMPILE AND RUN CODE INTO HTML.