diff --git a/.travis.yml b/.travis.yml
new file mode 100644
index 0000000..df13b4b
--- /dev/null
+++ b/.travis.yml
@@ -0,0 +1,4 @@
+language: cpp
+os: linux
+script:
+        - make
diff --git a/Inventory.cpp b/Inventory.cpp
index 57964b4..286fb27 100644
--- a/Inventory.cpp
+++ b/Inventory.cpp
@@ -5,6 +5,7 @@
 using std::string;
 using std::ostream;
   
+/*Constructor for an Inventory object*/
 Inventory::Inventory(string name, float price, int count)
 {
   m_name = name;
@@ -12,15 +13,25 @@ Inventory::Inventory(string name, float price, int count)
   m_in_stock = count;
 }
 
+/*Checking if an item is an stock and making a sale
+ *ultimately decreasing stock.
+ */
+
 void Inventory::sell()
 {
+  if(m_in_stock == 0){
+    std::cout<<"Sorry, that item is out of stock"<<std::endl;
+  }
+  else{
   m_in_stock--;
+  }
 }
 
+/*Transaction statement*/
 ostream& operator<<(ostream& stream, const Inventory& item)
 {
   stream << item.m_name 
          << " $"
          << std::fixed << std::setprecision(2) << item.m_price;
   return stream;
-}
\ No newline at end of file
+}
diff --git a/Inventory.h b/Inventory.h
index c52d5d8..55f5d78 100644
--- a/Inventory.h
+++ b/Inventory.h
@@ -5,6 +5,14 @@
 using std::string;
 using std::ostream;
 
+/*
+ * This class represents an Invetory of a shop
+ * Inventory holds 
+ *  -the name of an item
+ *  -the price and
+ *  -how much is left in stock
+ */
+
 class Inventory
 {
   private:
@@ -18,4 +26,4 @@ class Inventory
     friend ostream& operator<<(ostream&, const Inventory&);
 };
 
-#endif
\ No newline at end of file
+#endif
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..6219ecf
--- /dev/null
+++ b/README.md
@@ -0,0 +1,3 @@
+To build: type make into the command line
+
+to run type ./a.out