Ticket fields are custom fields that are typically used to gather more information about your Tickets. LiveAgent allows you to create unlimited custom Ticket fields.
When a customer reaches out to you about a problem with her or his order. By saving the Order ID in a custom Ticket field, you can save time by having this information available right in the Ticket information box.
When answering or editing a Ticket you can add more information to it by adding new Ticket fields with your own text.