Custom data fields
Out of the box (or more accurately, off the website), CiviCRM has a core set of fields for each type of record that handles the most fundamental and common needs of the system. Within the contact record, they include standard communication fields (phone, e-mail, website, and IM), address fields (street, city, state/province, country, county, and geocode), demographics (gender, birth date, and deceased date), communication preferences (do not mail, do not e-mail, preferred method of communication, and so on) and various additional fields. CiviCRM has a set of fields for each entity in the system, such as Event, Membership, and Contribution.
Whether you are migrating from an existing database or starting from scratch, you will inevitably have additional data you need to store in fields. CiviCRM provides for this need through its custom data tools.
Tip
Custom data is an incredibly powerful way to extend the database to meet the particular needs of your organization. However...