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Your responses to the short answer questions should be laid out here using Mark Down.

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Answers for Sprint Challenge

  1. Describe the differences between .forEach and map.
  • The difference is that map returns a new array and .forEach doesn't. .forEachjust operates all all values in the orginal array.
  1. Name five different types in JavaScript. What is so special about Arrays?
  • The five different types in JavaScript are:
  • object is an object is a value in memory which is referenced by an identifier. It associates a key with a value.
  • boolean represents a logicale entity and can have two values of true or false.
  • number is an numerical integer that has floating points.
  • string represents texual data and is enclosed with "" or ''. The indexes are zero based also.
  • undefined is a variable that has not been assigned a value yet. It is not the same as null or not definded.
  • An array can hold many values under a single name, and you can access the values by referring to an index number.
  1. What is closure? Can you code out a quick example of a closure?
  • A closure is an inner function that has access to the outer (enclosing) function's variables—scope chain. The closure has three scope chains: it has access to its own scope (variables defined between its curly brackets), it has access to the outer function's variables, and it has access to the global variables
  • example:
function inIt() {
    const name = "Mark"; // created local variable name
    function displayName() { // closure happens here at inner function
        console.log(name); // use variable declared in parent function
    }
    displayName();
}
inIt();
  1. Describe the four rules of the 'this' keyword.
  • The four rules of the this keyword are:
  1. Whenever a function is contained in the global scope, the value of this inside of that function will be the window object.
  2. When a function is called by a preceding dot, the object before the dot is this.
  3. Whenever a construction function is used, this refers to the specific instance of the object that is created and returned by the constructor function.
  4. Whenever JavaScipt's call or apply method is used, this is explicitly defined.