diff --git a/debugging/book-library/index.html b/debugging/book-library/index.html
index 23acfa7..1fb254f 100644
--- a/debugging/book-library/index.html
+++ b/debugging/book-library/index.html
@@ -69,6 +69,11 @@ <h1>Library</h1>
         />
       </div>
     </div>
+    <select id="sortSelect">
+      <option value="title">Sort by Title</option>
+      <option value="pages">Sort by Pages</option>
+    </select>
+    
 
     <table class="table" id="display">
       <thead class="thead-dark">
diff --git a/debugging/book-library/script.js b/debugging/book-library/script.js
index 75ce6c1..065c3b3 100644
--- a/debugging/book-library/script.js
+++ b/debugging/book-library/script.js
@@ -1,103 +1,112 @@
 let myLibrary = [];
 
-window.addEventListener("load", function (e) {
+window.addEventListener("load", function () {
   populateStorage();
   render();
 });
 
+function Book(title, author, pages, check) {
+  this.title = title;
+  this.author = author;
+  this.pages = pages;
+  this.check = check;
+}
+
 function populateStorage() {
-  if (myLibrary.length == 0) {
-    let book1 = new Book("Robison Crusoe", "Daniel Defoe", "252", true);
-    let book2 = new Book(
-      "The Old Man and the Sea",
-      "Ernest Hemingway",
-      "127",
-      true
-    );
-    myLibrary.push(book1);
-    myLibrary.push(book2);
-    render();
+  if (localStorage.getItem("myLibrary") === null) {
+    let book1 = new Book("Robinson Crusoe", "Daniel Defoe", 252, true);
+    let book2 = new Book("The Old Man and the Sea", "Ernest Hemingway", 127, true);
+    myLibrary.push(book1, book2);
+    saveToLocalStorage();
+  } else {
+    myLibrary = JSON.parse(localStorage.getItem("myLibrary"));
   }
 }
 
+function render(sortBy = null) {
+  const table = document.getElementById("display");
+
+  // Remove all rows except the header efficiently
+  while (table.rows.length > 1) {
+    table.deleteRow(1);
+  }
+
+  if (sortBy === "title") {
+    myLibrary.sort((a, b) => a.title.localeCompare(b.title));
+  } else if (sortBy === "pages") {
+    myLibrary.sort((a, b) => a.pages - b.pages);
+  }
+
+  myLibrary.forEach((book, index) => {
+    const row = table.insertRow();
+    const titleCell = row.insertCell(0);
+    const authorCell = row.insertCell(1);
+    const pagesCell = row.insertCell(2);
+    const wasReadCell = row.insertCell(3);
+    const deleteCell = row.insertCell(4);
+
+    titleCell.textContent = book.title;
+    authorCell.textContent = book.author;
+    pagesCell.textContent = book.pages;
+
+    const toggleReadButton = document.createElement("button");
+    toggleReadButton.className = "btn btn-success";
+    toggleReadButton.textContent = book.check ? "Yes" : "No";
+    wasReadCell.appendChild(toggleReadButton);
+
+    toggleReadButton.addEventListener("click", function () {
+      book.check = !book.check;
+      saveToLocalStorage();
+      render();
+    });
+
+    const deleteButton = document.createElement("button");
+    deleteButton.className = "btn btn-warning";
+    deleteButton.textContent = "Delete";
+    deleteCell.appendChild(deleteButton);
+
+    deleteButton.addEventListener("click", function () {
+      myLibrary.splice(index, 1);
+      saveToLocalStorage();
+      render();
+      alert(`You've deleted title: ${book.title}`);
+    });
+  });
+}
+
+function saveToLocalStorage() {
+  localStorage.setItem("myLibrary", JSON.stringify(myLibrary));
+}
+
+// Form elements
 const title = document.getElementById("title");
 const author = document.getElementById("author");
 const pages = document.getElementById("pages");
 const check = document.getElementById("check");
 
-//check the right input from forms and if its ok -> add the new book (object in array)
-//via Book function and start render function
 function submit() {
-  if (
-    title.value == null ||
-    title.value == "" ||
-    pages.value == null ||
-    pages.value == ""
-  ) {
-    alert("Please fill all fields!");
+  const titleValue = title.value.trim();
+  const authorValue = author.value.trim();
+  const pagesValue = pages.value.trim();
+
+  if (!titleValue || !authorValue || !pagesValue) {
+    alert("Please fill in all fields!");
     return false;
-  } else {
-    let book = new Book(title.value, title.value, pages.value, check.checked);
-    library.push(book);
-    render();
   }
-}
 
-function Book(title, author, pages, check) {
-  this.title = title;
-  this.author = author;
-  this.pages = pages;
-  this.check = check;
-}
+  const pagesNumber = Number(pagesValue);
 
-function render() {
-  let table = document.getElementById("display");
-  let rowsNumber = table.rows.length;
-  //delete old table
-  for (let n = rowsNumber - 1; n > 0; n-- {
-    table.deleteRow(n);
+  if (!Number.isInteger(pagesNumber) || pagesNumber <= 0) {
+    alert("Pages must be a positive whole number!");
+    return false;
   }
-  //insert updated row and cells
-  let length = myLibrary.length;
-  for (let i = 0; i < length; i++) {
-    let row = table.insertRow(1);
-    let titleCell = row.insertCell(0);
-    let authorCell = row.insertCell(1);
-    let pagesCell = row.insertCell(2);
-    let wasReadCell = row.insertCell(3);
-    let deleteCell = row.insertCell(4);
-    titleCell.innerHTML = myLibrary[i].title;
-    authorCell.innerHTML = myLibrary[i].author;
-    pagesCell.innerHTML = myLibrary[i].pages;
-
-    //add and wait for action for read/unread button
-    let changeBut = document.createElement("button");
-    changeBut.id = i;
-    changeBut.className = "btn btn-success";
-    wasReadCell.appendChild(changeBut);
-    let readStatus = "";
-    if (myLibrary[i].check == false) {
-      readStatus = "Yes";
-    } else {
-      readStatus = "No";
-    }
-    changeBut.innerText = readStatus;
-
-    changeBut.addEventListener("click", function () {
-      myLibrary[i].check = !myLibrary[i].check;
-      render();
-    });
 
-    //add delete button to every row and render again
-    let delButton = document.createElement("button");
-    delBut.id = i + 5;
-    deleteCell.appendChild(delBut);
-    delBut.className = "btn btn-warning";
-    delBut.innerHTML = "Delete";
-    delBut.addEventListener("clicks", function () {
-      alert(`You've deleted title: ${myLibrary[i].title}`);
-      myLibrary.splice(i, 1);
-      render();
-    });
-  }
+  const newBook = new Book(titleValue, authorValue, pagesNumber, check.checked);
+  myLibrary.push(newBook);
+  saveToLocalStorage();
+  render();
 }
+
+// Optional: Add sorting buttons
+document.getElementById("sortTitle").addEventListener("click", () => render("title"));
+document.getElementById("sortPages").addEventListener("click", () => render("pages"));