Text - a text field containing any text that may be typed or pasted from the clipboard. The values of a text field are displayed in the same way they are entered.
List - a text field with a limited and preset sets of values. For example, you may create a list of names of countries for the "Country" field, and then, during the data input, only select the necessary element from the drop-down list.
Date - a text field for date.
Checkmark - a field with two values allowed: "checked" and "not checked". For example, the "gender" field is usually drawn as two checkmarks with one of which you must check off.
Fields of different types have different color frames. You may change the frame colors on the General tab of the Options dialog (View>Options) in the Appearancegroup. Select the necessary object in the Item field and then the necessary color in the Color field.