Pen and Dots

There are two basic variations to the dottin system, one used by beginners and intermediates, and the other preferred by the more advanced.
The first one that uses, different dots and draws a line round the cell "locking it", you may say.
It is very helpful tool to many, by providing easy access information.
The other technique is the preferred of the purists, while working with mainly advanced formats.
In this instance the graphic patterns of the dots are not interfered with.
In this variation all the dots are the same size, (I know of one person that actually uses a white-out pen to maintain the cells only with valid POPs).
The purpose here is to show the patterns in it's purest schematic face, for better adivination.