Normalization is a process used to organize a database into tables and columns.  The main idea with this is that a table should be about a specific topic and only supporting topics included. Take a spreadsheet containing the information as an example, where the data contains salespeople and customers serving several purposes:

• Identify salespeople in your organization
• List all customers your company calls upon to sell a product
• Identify which salespeople call on specific customers.

By limiting a table to one purpose you reduce the number of duplicate data contained within your database. This eliminates some issues stemming from database modifications.