Within entity items, the data is stored in individual <em>fields</em>, each of which holds one type of data, such as formatted or plain text, images or other files, or dates. Fields can be added by an administrator on entity sub-types, so that all entity items of a given entity sub-type have the same collection of fields available, and they can be single-valued or multiple-valued. When you create or edit entity items, you are specifying the values for the fields on the entity item.