When we define an individual line for our selection screen, we need to define the start and end of each line In between the start and end, we include the specific parameters and select option statements. Everything between the begin and end will appear on one line. Need to get positioning and length parameters correct. Whenever you use BEGIN OF LINE and END OF LINE, the selection text that describes the parameter element is not displayed. That is when you need comments to create own description of the line. POSITION addition can only be used at BEGIN OF LINE or END OF LINE. Lets you define the position of the next element separately. Different elements allow you to specify their positions with their own syntax, so do not use POSITION addition too much. Specify the position using an integer.