Mandatory or optional field name

1. What does optional field mean?
2. What are mandatory fields?
3. How do you indicate optional fields?

What does optional field mean?

Optional fields are not required to save the credit as complete and have no impact on scoring. They are included to give participants the opportunity to provide additional context.

What are mandatory fields?

When a mandatory field is available in the form, it means user should fill that field without fail. Leaving the mandatory fields will cause in non submission of the form.

How do you indicate optional fields?

Add (optional) at the end of the label

The best way to indicate optional is to add the word in parenthesis after the label. It's easy to read and visually connected to the label that it is referring to.