diff --git a/04week/loop.js b/04week/loop.js
index e69de29bb..ba9718fec 100644
--- a/04week/loop.js
+++ b/04week/loop.js
@@ -0,0 +1,36 @@
+const carsInReverse = ['Ford', 'Honda', 'BMW', 'Lexus'];
+for (let index = carsInReverse.length - 1; index > -1; index--) {
+  console.log(carsInReverse[index]);
+}
+
+const person = {
+  firstName: "Jane",
+  lastName: "Doe",
+  birthDate: "Jan 5, 1925",
+  gender: "female"
+}
+for (const key in person) {
+  console.log(person[key]);
+}
+
+for (const key in person) {
+  if (key === "birthDate") {
+    console.log(person.birthDate);
+  }
+}
+
+let number = 0;
+while (number < 1000) {
+  number++;
+  console.log(number);
+}
+
+let number = 0;
+do {
+  number++;
+  console.log(number);
+} while (number < 1000);
+
+/* A for loop is better than a while loop when you know the number of iterations.
+A for...in loop is used with objects only.
+A do while loop always runs once before testing the conditional. The while loop tests the conditional first. */
\ No newline at end of file