diff --git a/InterviewQuestions/findSecondLargestElementInArray.js b/InterviewQuestions/findSecondLargestElementInArray.js
new file mode 100644
index 0000000..088e6ed
--- /dev/null
+++ b/InterviewQuestions/findSecondLargestElementInArray.js
@@ -0,0 +1,20 @@
+/**
+ * Problem statement: Find second largest element in the array. Consider the case wherein duplicates can exist
+ * arr = [12, 35, 1, 10, 34, 35, 35] - Here 35 occurs 3 times, but second largest element should be 34
+ */
+function findSecondLargestElementInArray(arr) {
+  let largest = -1,
+    secondLargest = -1;
+
+  for (let i = 0; i <= arr.length - 1; i++) {
+    if (arr[i] > largest) {
+      secondLargest = largest;
+      largest = arr[i];
+    } else if (arr[i] > secondLargest && arr[i] != largest) {
+      secondLargest = arr[i];
+    }
+  }
+  console.log(secondLargest);
+}
+let arr = [12, 35, 1, 10, 34, 35, 35];
+findSecondLargestElementInArray(arr);
diff --git a/ReferenceBooks/JavaScript-The-Definitive-Guide-Master-The-Worlds-Most-Used-Programming-Language-7th-Edition.pdf b/ReferenceBooks/JavaScript-The-Definitive-Guide-Master-The-Worlds-Most-Used-Programming-Language-7th-Edition.pdf
new file mode 100644
index 0000000..1ee9fdd
Binary files /dev/null and b/ReferenceBooks/JavaScript-The-Definitive-Guide-Master-The-Worlds-Most-Used-Programming-Language-7th-Edition.pdf differ
diff --git a/Snippets/Strings/lowerCaseConverter.js b/Snippets/Strings/lowerCaseConverter.js
new file mode 100644
index 0000000..6c88127
--- /dev/null
+++ b/Snippets/Strings/lowerCaseConverter.js
@@ -0,0 +1,7 @@
+// toLowerCase() method changes the string to lowercase letters.
+let favLanguage = "JavasCript";
+console.log(favLanguage.toLowerCase()); // javascript
+let standard = "ECMA";
+console.log(standard.toLowerCase()); // ecma
+let oneMoreLangugae = "PHP";
+console.log(oneMoreLangugae.toLowerCase()); // php
diff --git a/Snippets/Strings/upperCaseConverter.js b/Snippets/Strings/upperCaseConverter.js
new file mode 100644
index 0000000..3a6acf9
--- /dev/null
+++ b/Snippets/Strings/upperCaseConverter.js
@@ -0,0 +1,7 @@
+// toUpperCase() method changes the string to upper letters.
+let favLanguage = "JavasCript";
+console.log(favLanguage.toUpperCase()); // JAVASCRIPT
+let firstName = "ECMA";
+console.log(firstName.toUpperCase()); // ECMA
+let oneMoreLangugae = "Python";
+console.log(oneMoreLangugae.toUpperCase()); // PYTHON