diff --git a/main.js b/main.js
index 220d2e1..9a1b94d 100644
--- a/main.js
+++ b/main.js
@@ -1 +1,66 @@
 // write your code here to make the tests pass
+var Library = function() {
+  var books = [];
+
+  var addBook = function(book) {
+    books.push(book);
+  }
+
+  var checkOutBook = function(book) {
+    for(i=0; i < books.length; i++) {
+      if(book.title === books[i].title) {
+        var checkedOut = books[i].getAttribute('checkedOut')
+        if(!checkedOut) {
+          books[i].setAttribute('checkedOut', true);
+        }
+        else console.log('error in check out');
+      }
+    }
+  }
+
+  var returnBook = function(book) {
+    for(i=0; i < books.length; i++) {
+      if(book.title === books[i].title) {
+        var checkedOut = books[i].getAttribute('checkedOut');
+        if(checkedOut) {
+          books[i].setAttribute('checkedOut', false);
+        }
+        else console.log('error in return');
+      }
+    }
+  }
+
+  return {
+    addBook: addBook,
+    checkOutBook: checkOutBook,
+    returnBook: returnBook
+  }
+
+}
+
+var Book = function(title, author){
+
+  var attributes = {
+    title: title,
+    author: author,
+    checkedOut: false
+  }
+
+  var getAttribute = function(attribute) {
+    if (attribute ) {
+      return attributes[attribute];
+    }
+  }
+
+  var setAttribute = function(attribute, value) {
+    if (attribute in attributes) {
+      attributes[attribute] = value;
+    }
+  }
+
+
+  return {
+    getAttribute: getAttribute,
+    setAttribute: setAttribute
+  }
+}