Understanding Scope
In computer science, scope is the region of a computer program where the binding or association of a name to an entity, such as a variable or function, is valid. JavaScript has the following two distinct types of scope:
- Function scope
- Block scope
Until ES6, function scope was the only form of scope in JavaScript; all variable and function declarations followed function scope rules. Block scope was introduced in ES6 and is used only by the variables declared with the new variable declaration keywords let and const. These keywords are discussed in detail in the Declaring Variables section.
Function Scope
Function scope in JavaScript is created inside functions. When a function is declared, a new scope block is created inside the body of that function. Variables that are declared inside the new function scope cannot be accessed from the parent scope; however, the function scope has access to variables in the parent scope...
