Bind call and apply

They are functions which function objects have.
Allows you to create preset function with arguments.

• Call: Allows you to set this variable.
• Apply: Similar to call but expects arguments as an array.
• Bind: Also allows you to set the this variable. However, it does not execute the function immediately but generates a copy of the function which can be stored.

var john = {
  name: "John",
  age: 26,
  job: "Teacher",
  presentation: function(style, timeOfDay) {
    if (style === "formal") {
      console.log(
        "Good " +
          timeOfDay +
          ", Ladies and gentlemen! I'm " +
          this.name +
          ", I'm a " +
          this.job +
          " and I'm " +
          this.age +
          " years old"
      );
    } else if (style === "friendly") {
      console.log(
        "What's up? My name is " +
          this.name +
          ", I'm a " +
          this.job +
          " and I'm " +
          this.age +
          " years old"
      );
    }
  }
};

var emily = {
  name: "Emily",
  age: 35,
  job: "designer"
};

john.presentation("formal", "morning");

john.presentation.call(emily, "friendly", "afternoon");

// This is currying
var johnFriendly = john.presentation.bind(john, "friendly");

johnFriendly("afternoon");

Currying

Creating a function from another function but with some preset parameters.