diff --git a/main.js b/main.js
index 220d2e1..86961c4 100644
--- a/main.js
+++ b/main.js
@@ -1 +1,78 @@
-// write your code here to make the tests pass
+/*
+  This is a factory function that returns a library object with 3 methods:
+  library.addBook(bookObj)  - adds a book to the books array
+  library.checkoutBook(bookObj)  - checks out a book
+  library.returnBook(bookObj)   - checks in a book  
+ */
+var Library = function() {
+  var books = [];
+
+  //this adds a book object to the books array
+  var addBook = function(book) {
+    books.push(book);
+  }
+
+  //this function will check-out a book if it exists in the books array 
+  var checkOutBook = function(book) {
+    if (books.includes(book)) {
+      book.setAttribute('checkedOut', true);
+    } else {
+      console.log('This book is not available at this library');
+    }
+  };
+
+  //this function will check-in a book if it exists in the books array 
+  var returnBook = function(book) {
+    if (books.includes(book)) {
+      book.setAttribute('checkedOut', false);
+    } else {
+      console.log('This book is not available at this library');
+    }
+  };
+
+  //this returns the library object with 3 methods to manipulate the books array
+  return {
+    addBook: addBook,
+    checkOutBook: checkOutBook,
+    returnBook: returnBook
+  };
+}
+
+/*
+This is a factory function that returns a book object with 2 methods:
+book.getAttribute('title')   - returns the title
+book.setAttribute('checkedOut', true)  - changes checkout status
+*/
+var Book = function(title, author) {
+  //this obj stores 3 properties on a new book 
+  //title argument is required create/return book object
+  if (title) {
+    var attributes = {
+      title: title,
+      author: author || null, //null if author argument is absent
+      checkedOut: false
+    }
+  } else {
+    return console.log('Book title is required!');
+  }
+
+  //if the attribute exists on the book, this will return the value
+  var getAttribute = function(attribute) {
+    if (attributes[attribute] !== undefined) {
+      return attributes[attribute];
+    }
+  };
+
+  //if the attribute exists on the book, this will reset the value
+  var setAttribute = function(attribute, value) {
+    if (attributes[attribute] !== undefined) {
+      attributes[attribute] = value;
+    }
+  }
+
+  //this returns the book object with 2 methods to access the attributes
+  return {
+    getAttribute: getAttribute,
+    setAttribute: setAttribute
+  };
+};
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