Force.com is an object-oriented relational database system. An object is the background of any application built on Force.com. An object is like a database table that allows you to store data in different formats. It also gives you options to create a UI in order to enter, modify, or delete records.
Force.com doesn't give you the option to create database tables using code. To create a table, we need to define the object using the UI. The UI not only allows you to define the object definition but also comes with unique built-in features, including recording activities (such as logging a call, sending an e-mail, and so on) and the ability to add notes and attachments. The platform automatically creates a standard UI for the object thus defined and adds basic features, such as create, update, and delete.