User defined fields are custom fields that can be used to collect information specific to the organization needs. User Defined Field cannot store historic data hence, any changes to these fields in Web TimeSheet, at any given point of time cannot be tracked based on their effective dates when the change took place. For example, add a user defined field of type Text under the User section and update the field by adding some value to this text field under any user's profile. Later, when value is changed by any other administrators in the application then the change cannot be tracked based on what date the change was made or what value was changed.