Some of the control type statements allow you to identify the name of a specific point in an ILF routine where control passes. This name is called a label. You often use labels to cause a branching operation to be performed. For example:
The label :CALCTOTAL refers to the name of a section of the ILF routine to execute next. In this example, APPX passes processing control to the label :CALCTOTAL if the first internal true/false status indicator has a value of T.
Note that the label in our example begins with a colon. This is because many programmers find a colon helps to make a label name stand out from ordinary field names but there is no requirement to use a colon.