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JavaScript JavaScript and the DOM (Retiring) Getting a Handle on the DOM A Simple Example


What is the const keyword? and what it's the use of it?.

1 Answer

Steven Parker
Steven Parker
220,450 Points

It is similar to "let", in that it creates a variable limited to the current scope. But a "const" variable can only be assigned at the same time it is created, and it's value cannot be changed later.

It is considered good practice to use const any time a variable will not be changed by the program during its lifetime. Examples:

let sample = 3;
const steady = 4;
sample = 7;  // this is OK
steady = 9;  // this causes an error

Thank you, Steven,