▁derived ▁( in her ited ) ▁from ▁the ▁super class ▁and ▁then ▁it ▁has ▁its ▁own ▁set ▁of ▁functions ▁and ▁data . ▁Interface ▁( object - orient ed ▁programming ): ▁The ▁ability ▁to ▁de fer ▁the ▁implementation ▁of ▁a ▁method . ▁The ▁ability ▁to ▁define ▁the ▁functions ▁or ▁methods ▁sign atures ▁without ▁implementing ▁them . ▁Pol ym orphism ▁( specific ally , ▁Sub ty ping ): ▁The ▁ability ▁to ▁replace ▁an ▁object ▁with ▁its ▁sub objects . ▁The ▁ability ▁of ▁an ▁object - variable ▁to ▁contain , ▁not ▁only ▁that ▁object , ▁but ▁also ▁all ▁of ▁its ▁sub objects . ▁ ▁Design ing ▁concepts ▁ ▁Def ining ▁objects , ▁creating ▁class ▁diagram ▁from ▁concept ual ▁diagram : ▁Usually ▁map ▁entity ▁to ▁class . ▁ ▁Ident ifying ▁attributes . ▁ ▁Use ▁design ▁patterns ▁( if ▁applicable ): ▁A ▁design ▁pattern ▁is ▁not ▁a ▁finished ▁design , ▁it ▁is ▁a ▁description ▁of ▁a ▁solution ▁to ▁a ▁common ▁problem , ▁in ▁a ▁context . ▁The ▁main ▁advantage ▁of ▁using ▁a ▁design ▁pattern ▁is ▁that ▁it ▁can ▁be ▁re used ▁in ▁multiple ▁applications . ▁It ▁can ▁also ▁be ▁thought ▁of ▁as ▁a ▁template ▁for ▁how ▁to ▁solve ▁a ▁problem ▁that ▁can ▁be ▁used ▁in ▁many ▁different ▁situations ▁and / or ▁applications . ▁ ▁Object - orient ed ▁design ▁patterns ▁typically ▁show ▁relationships ▁and ▁interactions ▁between ▁classes ▁or ▁objects , ▁without ▁specifying ▁the ▁final ▁application ▁classes ▁or ▁objects ▁that ▁are ▁involved . ▁ ▁Define ▁application ▁framework ▁( if ▁applicable ): ▁Application ▁framework ▁is ▁usually ▁a ▁set ▁of ▁libraries