When you label your map automatically, or interactively using the Label tool, the content of the labels is determined by the data associated with the geographic object. You can obtain the labels from the columns in your table, or the derived result of an expression using the column information. If the column information or an expression does not suit your needs, you can edit the label content or type in new text. See Labeling Interactively for more information.
Text you create yourself using the Label Tool (on the MAP tab) is a text object and behaves like other objects you draw on your map such as squares and circles. Although labels and text objects behave somewhat differently, text objects are still useful for additional map annotation such as titles. For information on text objects, see Working with Text on the Map.