Departmental undertakings are those public sector enterprises that are established as departments of the ministry and are considered part or an extension of the ministry itself. Examples of these undertakings are Railways, Post and telegraph department.

1. Employement: Employment is an agreement between an employer and an employee that the employee will provide certain services. In return, the employee is paid a salary or hourly wage. Although employees can negotiate certain items in an employment agreement, the terms and conditions are primarily determined by the employer. Both parties may also terminate the agreement.
2. The profession includes those activities, which are requiring special knowledge and skill to be applied by individuals in their occupation to earn fees. A professional also takes a minimal risk of whether he will get clients or not.
3. Business refers to those economic activities, which are connected with production, purchase, and sale of goods or supply of services with the main object of earning a profit. Since there is no pre-determined contract, return which is profit, is not fixed. There may be profits in millions or there may be a heavy loss. Therefore, business as an economic activity is different from other economic activities mainly due to profit. However, there are other differences as well. For example, a businessman does not need specific qualifications as required in a profession. A businessman has relatively more freedom than a person who is employed or is a professional.