The initials consist of the first letter of the first name and the first letter of the last name. The initials are automatically loaded by the system when you have entered both the first and last names. You can enter other initials if you want, by just overwriting the existing initials. This field can contain up to four alphanumeric characters.
Certain procedure make references to a particular employee (such as Manufacturing Order Info), but the reference has to fit in a very small field. That is when the initials are useful. That is why it may come in handy to use initials that are easy to link to the person.