I need a full Descreption for the title, including : when should we use this method? why should we use it? under which circumestances we should choose this method? what are the processes of...

I need a full Descreption for the title, including : when should we use this method? why should we use it? under which circumestances we should choose this method? what are the processes of implementing? does it have any sub category? if yes, please list the titles.