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JavaScript JavaScript Basics (Retired) Storing and Tracking Information with Variables Capturing Visitor Input

Posted by Cole Mckeon
Cole Mckeon
Courses Plus Student 641 Points

When do you use camelCase and when do you use under_score?

Is camel case or under scores only used for functions and variables? What determines when someone would chose to use one over the other.

clickpass
clickpass
23,992 Points

Many programmers follow AirBNB naming conventions. Here is a link to their page about variable naming conventions: https://github.com/airbnb/javascript#variables

Use camelCase when naming objects, functions, and instances.

Use PascalCase only when naming constructors or classes.

1 Answer

Steven Parker
Steven Parker
231,275 Points
Steven Parker
Steven Parker
231,275 Points

The most common convention is to use camelCase (starting with a lower-case character) for both variable and function names, and PascalCase (starting with a capital letter) for class names.

Another, but slightly less universal convention, is to name constants using ALL_CAPS with underscores.

Private variable names are sometimes started with an underscore, but are otherwise camelCase.

Lower-case names with underscore word separators (also known as snake_case) is popular in some other languages, but not a typical convention in JavaScript.