Define Variables with let and const

ES2015 introduced two new keywords for declaring variables: const and let. Both work similarly to var. You use the keyword -- const or let -- and a value you want to put into the variable: let message = "Hello"; const pi = 3.14159; let score = 0; const is short for constant, meaning that the value of the variable shouldn't change -- it should remain "constant". const protects a variable from...