javascript function declaration vs arrow function

1function timesTwo(params) {  return params * 2}function timesTwo(params) {
2  return params * 2
3}
4
5timesTwo(4);  // 8

1Regular functions created through function declarations / expressions are both constructible and callable. ... Arrow functions (and methods) are only callable i.e arrow functions can never be used as constructor functions. Hence, they can never be invoked with the new keyword.