You can set breakpoints only for lines that execute. You can't set a breakpoint on lines that declare user data types or contain only remarks.
As your applications execute, you might want to set breakpoints along the way. The breakpoints halt the program's execution so that you can study variables and controls during mid-execution. For example, if you see runtime problems that you want to analyze on the next program run, add a breakpoint by clicking the Debug toolbar's Toggle Breakpoint button at the highlighted statement. You can set multiple breakpoints on additional lines by clicking the Toggle Breakpoint button throughout the code. If you reach a breakpoint (indicated by a red highlight) that you set in a previous session but no longer need, use Toggle Breakpoint again on that line to remove the breakpoint from that location.
You can set breakpoints only for lines that execute. You can't set a breakpoint on lines that declare user data types or contain only remarks.