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JavaScript Hoisting

 Hoisting JavaScript Hoisting refers to the process where the interpreter allocates memory for variables and function declarations prior to the execution of the code. Declarations that are made using the var keyword are initialized with the default value of undefined Declarations made using the let and the const keywords are not initialized as a part of the hoisting  Hoisting takes place during the creation phase of the Execution Context. consider the following script:  output: undefined Steps involved in the execution of the above script: A new Global Execution Context is created. num variable is initialized with undefined . In the execution phase, the code is executed line-by-line. In the first line it logs undefined to the console. Line two is skipped as it already defined num in the creation phase. In line three a value of 6 is assigned to num. let and const keywords let and const keywords are hoisted but not initialized Consider the following script:  output: ReferenceError: