differentiation.txt

1. As long as the items are added to the cart,  our back end server would examine the inventory immediately because 
   the customer shows the intention to buy. If the inventory is not enough, we would send request to world to ask 
   for more products in this kind . By doing this, we would save the some time in preparation when the customer 
   officially place his/her orders. 

2. We will add 10 times number of products of its original required quantity because pre-load enough products in the 
   warehouse would save much time when similar order appears. In our first designing, we asked for purchasing exactly 
   the amount of products each time the user wants to buy. This will cause the program spend a lot of time to contact
   the world for more products. In our new design, Roughly, we reduced the time of contacting the world to a small scale.

3. For the user's convience, the users should be able to modify the products they added into their cart. In the minimum 
   requirements, we are not asked to do that. So, we used a DeleteView module in django, and designed the "remove" function
   for all the products in users' carts. If they want, they can delete any products they added into their carts.

   We also add a function that allows the users to modify the count of their products in their carts. It is called 
   "update" in our page. If the user choose to update their products in cart, they can modify the the count of the 
   products they chose.

4. The front end and back end are totally separated, and only the backend would be able to modify the database, which 
   make less conflict and make queries and changing much more clear and straightforward. We requires the frontend (django)
   only has the ability to read from the database. Each time the frontend has the request for modifying the database,
   the frontend will send a request using our self-defined protocal between the frontend and the backend.