INTRODUCTION OF ROBBIN'S DEFINATION: The concept of material welfare was rejected by professor robbin's becauseit is defective and non scientific. Robbin's in1932 in his book(AN EASSAY ON THE NATURE AND THE SIGNIFICANCE OF ECONOMIC SCIENCE) critisize the marshall's defination and gave his own defination ,according to robbin's economics is a science which studies human behaviour as a relation between ends and scarce resources r means which have alternative uses. MAIN FEATURE OF ROBBIN'S DEFINATION: robbin's defination based on following facts 1:Unlimited wants 2:Limited resources 3:Alternative uses of means 4:Wants have different importance 1:UNLIMITED WANTS: the man feel wants and there is no limit to end there wants . Wants create a problem of choices when the first want is satisfies other arises to take its place 2:LIMITED RESOURCES: secondly the time and the resources are available to satisfy there wants. Wants are limited and create a problem of scarcity here the term scarce is used in a special sense means a community may exists in a smalll quantity. 3:ALTERNATIVE USES OF MEANS: the third impliment of this defination is that the scarce means are capable of alternative uses FOR EXAMPLE:a piece of land may be used to grow crops or to build house or as a play ground 4:WANTS HAVE DIFFERENT IMPORTANCE: ends are not of equal importance some ends are more important then other. People arrange there want in ordered of prefrence FOR EXAMPLE: Food is most important than a pen or a book. So efforts to get a pen can be made only when one has no fear of hunger.