Business definition is a strategic process where firms select unique positions in their industry to gain competitive advantages. It involves creatively defining the firm's focus and objectives. Successful business definition results in the firm concentrating its efforts on key areas while avoiding unnecessary activities. It also provides direction and motivation for other strategic decisions. Over time, the optimal focus may need to shift from narrow to broad as industries mature and the competitive landscape changes, requiring periodic reevaluation and redefinition of the business.