feat: add funciton in depth

Author: ExploitEngineer

part3 (Fundamental Concepts)/functions_deeply.js

@@ -0,0 +1,25 @@
+// Function Statement aka Function Declaration
+a();
+function a() {
+  console.log("a called");
+}
+
+// Function Expression
+let b = function () {
+  console.log("b called");
+};
+b();
+
+// Anonymous Funtions
+let c = function () {
+  console.log("anonymous function");
+};
+
+// Named Function Expression
+let d = function abcd() {
+  console.log("Named function expression");
+};
+
+// First Class Functions
+// the functions which we can pass to another function pass as  a value, can be returned from another function is called frist class functions.
+