Line Labels
Source: Positron16 Compiler User Manual, PDF page 19
In order to mark statements that the program may wish to reference with the GoTo, Call, or Gosub commands, the compiler uses line labels. Unlike many older BASICs, the compiler does not allow or require line numbers and doesn’t require that each line be labelled. Instead, any line may start with a line label, which is simply an identifier followed by a colon ':'.
Label:
Print "Hello World"
GoTo Label