• Hoisting in JavaScript
• Var, let and const
• Temporal dead zone
• lexical scope
• Higher-Order Functions
  • Functions that operate on other functions, either by taking them as arguments or by returning them, are called higher-order functions
• Shallow copy and Deep copy
• Difference B/W These functions
  • Function Expression
  • Function Declaration
  • Function Statement
  • Anonymous Function
  • Named Function Expression
  • First Class Functions
    • A programming language is said to have First-class functions when functions in that language are treated like any other variable.
    • JavaScript

      const foo = function() {   console.log("foobar"); } foo(); // Invoke it using the variable // foobar

      1	const foo = function() {   console.log("foobar"); } foo(); // Invoke it using the variable // foobar

  • Arrow Functions
• Currying
  • Currying is an advanced technique of working with functions.
  • Currying is a transformation of functions that translates a function from callable as f(a, b, c) into callable as f(a)(b)(c).
• Template literals
  • JavaScript

    var rgb = rgb(${r}, ${g}, ${b});

    1	var rgb = rgb(${r}, ${g}, ${b});

• What is closure?
  • A closure is the combination of a function bundled together (enclosed) with references to its surrounding state (the lexical environment).
  • In other words, a closure gives you access to an outer function’s scope from an inner function.
• Spread syntax
• Object de-structuring
• Map vs ForEach, Find vs filter
• Exception handling
• Event Loop
• Promise, async, wait
• TypeScript
• O.O.P.
• Threads
  • Execution Thread
    • Execution Thread is a thread of execution in a single JavaScript file.
  • Worker Thread
    • Worker Thread is a thread of execution in a single JavaScript file.
  • Cluster
    • Cluster is a group of computers that are connected to a single network.

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