Scope Chain: The concept of the "scope chain" describes how JavaScript searches for variable references by traversing through nested scopes until it finds the desired variable.
Block Scope: Block scope is similar to local scope but specifically refers to variables declared within curly braces ({}) in languages like JavaScript or C++. These variables are only accessible within that specific block.
Function Scope: Function scope is a type of local scope that applies specifically to variables declared inside functions. These variables exist only within the function and cannot be accessed outside of it.