What's a Data Model ?

A Data Model is a document that summarizes all the data your application is going to manage.

Here's a relatively simple Data Model that would fit the core features of facebook:

In this example, the boxes are "items", and the arrows are "relations" between these items.
They've been given names to explain their purpose in terms of features users can see.

A Data Model also includes information about whether a Message can be sent by only one User, or to only one User.

And lastly, it includes all the information bits that are gathered for every "item", e.g. for Users, we'd like to have their first name, last name, email, mobile number and date of birth.

If you don't have a Data Model yet / would like assistance with creating one, click here.