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The scope of a var variable is functional scope. We can redeclare, reassign or modify a varvariable.
The scope of a let variable is block scope. We can modify the value of let variable.
The scope of a const variable is block scope. It can not be updated and re-declared into the scope.

Regular functions created using function declarations or expressions are constructible and callable. Since regular functions are constructible, they can be called using the new keyword. However, the arrow functions are only callable and not constructible, i.e arrow functions can never be used as constructor functions.

.map() executes the same code on every element in an array and returns a new array with the updated elements.
.forEach(), is used to execute the same code on every element in an array but does not change the array and it returns undefined.
.filter() checks every element in an array to see if it meets a certain criteria and returns a new array with the elements that return truthy for the criteria.
.find() method returns the first element in the provided array that satisfies the provided testing function. If no values satisfy the testing function, undefined is returned.

Template strings are a powerful feature of modern JavaScript released in ES6. It lets us insert/interpolate variables and expressions into strings without needing to concatenate like in older versions of JavaScript. It allows us to create strings that are complex and contain dynamic elements