Binding

In programming, abindingis an association of anidentifierwith a value. Not all bindings arevariables— for example, functionparametersand the binding created by thecatch (e)block are not "variables" in the strict sense. In addition, some bindings are implicitly created by the language — for example,thisandnew.targetin JavaScript.

A binding ismutableif it can be re-assigned, andimmutableotherwise; this doesnotmean that the value it holds is immutable.

A binding is often associated with ascope.Some languages allow re-creating bindings (also called redeclaring) within the same scope, while others don't; in JavaScript, whether bindings can be redeclared depends on the construct used to create the binding.