Define motivation,and differentiate between need theories of motivation and process theories of motivation.

Motivation can be defined as the set of processes that account for the direction,level,and persistence of a person's effort toward attaining some goal.There are several theories of work motivation,all of which are concerned with the reasons,other than ability,that some people perform their jobs better than others.Need theories of motivation are concerned with what motivates people-that is,the categories of needs that people are motivated to satisfy (e.g.,safety needs and esteem needs),whereas process theories of work motivation focus on how motivation occurs.One such process theory is equity theory,which postulates that employees are motivated to achieve a condition of equity or fairness in their dealings with other people and with their organizations.