Examples of government companies are:
(i) Coal Mines Authority Ltd.,
(ii) Steel Authority of India Ltd.,
(iii) Indian Telephone Industries,
(iv) Tamil Nadu State Transport Corporation Ltd.,
(v) Tamil Nadu Agro Industries Corporation (Jointly Owned by Central State Govt.),
(vi) Tamil Nadu Small Industries of India Corporation (TANSI),etc.,

Examples of public corporations are:
(i) Reserve Bank of India
(ii) Damodar Valley Corporation
(iii) State Trading Corporation
(iv) Industrial Development Bank of India
(v) Industrial Finance Corporation
(vi) Life Insurance Corporation, etc.,

According to S.S.Kher, State Enterprises are "The industrial, commercial and economic activities carried on by the central or by a state government and in each case either solely or in association with private enterprise, so long it is managed by self-contained management."

S.No	Company	Headquarter
(i)	Coal India Ltd	Kolkata
(ii)	Steel Authority of India Ltd	New Delhi
(iii)	Tamil Nadu State Transport Corporation Ltd	Chennai
(iv)	Gas Authority of India Limited	New Delhi

i. Departmental undertakings is the form of public enterprises which is most suitable for projects related to National Security
ii. Because Strategic industries like defence and atomic power cannot be better managed other than government departments.
iii. Department undertakings can maintain secrecy in their working.

A departmental undertaking is established either as a separate full - fledged ministry or as a major sub-division of a ministry (i.e. department) of the Government.

(i) Departmental undertakings
(ii) Statutory corporations
(iii) Government company
(iv) Board organisation

A public corporation is an autonomous body corporate created by a special statute of a state or central government. A public corporation is a separate legal entity created for a specific purpose. It is administrated by a Board appointed by public authority to which it is answerable.

Strategic industries like defence and atomic power cannot be better managed other than government departments. Department undertakings can maintain secrecy in their working. So for the security of the country defence industry are always owned and controlled by departmental undertaking.

A "Government Company" is defined under Section 2(45) of the Companies Act, 2013 as "any company in which not less than 51% of the paid-up share capital is held by the Central Government, or by any State Government or Governments, or partly by the Central Government and partly by one or more State Governments, and includes a company which is a subsidiary company of such a Government company".

1. Departmental organisations - Indian Railways, Food and Public distribution.
2. Public organisations - Food Corporation of India FCI, ONGC, Oil and Natural Gas Corporation.
3. Government companies - Steel Authority of India Ltd, Tamilnadu Transport Corporation.
4. Board organisations - Tamil Nadu Electricity Board, Tamil Nadu Slum Clearance Board.

Following are the areas where the state or central ownership is a preferred form of business organisation:
1. the place where raw materials are available
2. the place where suitable workers are found
3. the place where transportation facilities like roadways, railways, shipping and airways are readily available.
4. The place where political stability is determined.

Features of Departmental Undertaking:
The salient features of a departmental undertaking are as follows:
a) Formation:
A departmental undertaking is established either as a separate full-fledged ministry or as a sub-division of a ministry (i.e. department) of the Government.
b) No Separate Entity:
A departmental undertaking does not have an independent entity distinct from the Government.
c) Governmental Financing:
The departmental undertaking is financed, through annual budget appropriations by the Parliament or the State Legislature. The revenues of the undertaking are paid into the government treasury.
d) Accounting and Audit:
The departmental undertaking is subject to the normal budgeting, accounting and audit procedures, which are applicable to all Government departments.
e) Managed by Civil Servants:
The departmental undertaking is managed by civil servants, who are subject to same service conditions as applicable to civil servants of the Government.

Features of Government Company:
a) Registration Under the Companies Act:
A Government company is formed through registration under the Companies Act, 1956, and is subject to the provisions of this Act, like any other company.
However, the Central Government may direct that any of the provisions of the Companies Act shall not apply to a Government company or shall apply with certain modifications.
b) Executive Decision of Government:
A Government company is created by an executive decision of the Government, without seeking the approval of the Parliament or the State Legislature.
c) Separate Legal Entity:
A Government company is a legal entity separate from the Government, It can acquire property; can make contracts and can file suits, in its own name.
d) Whole or Majority Capital Provided by Government:
The whole or majority (at least 516) of the capital of a Government company is provided by the Government; but the revenues of the company are not deposited into the treasury.
e) Majority of Government Directors:
Being in possession of a majority of share capital, the Government has authority to appoint majority of directors, on the Board of Directors of a government company.

Advantages of Departmental Undertaking;
Following are the advantages of the departmental undertaking.
a) Easy Formation:
It is easy to set up a departmental undertaking. The departmental undertaking is created by an administrative decision of the Government, involving no legal formalities for its formation.
b) Direct and Control of Parliament or State Legislature:
The departmental undertaking is directly responsible to the Parliament or the State legislature through its overall head i.e. the minister concerned.
c) Secrecy Maintained :
Strategic industries like defence and atomic power cannot be better managed other than government departments. Department undertakings can maintain secrecy in their working.
d) Lesser Burden of Tax on Public :
Earnings of departmental undertaking are entirely paid into Government treasury, resulting in lesser tax burden on the public.
e) Instrument of Social Change :
Government can promote economic and social justice through departmental undertakings. Hence, a departmental undertaking can be used by the Government, as an instrument of social change,
Disadvantages of Departmental Undertaking:
Following are the major limitations of the departmental undertaking.
a) Red-Tapism:
There is too much of procedures which results in delay. Commercial organisation cannot afford delay in taking decisions.
b) Incidence of Additional Taxation:
Losses incurred by a departmental enterprise are met out of the treasury.
This very often necessitates additional taxation the burden of which falls on the Common man.
c) Lack of Competition:
Civil Servants are given control of these undertakings who may not have business outlook or commercial experience. So, they run the undertaking in their own fashion without considering the sovereignty of the consumers.
d) Casual Approach to Work:
As officers of a departmental undertaking are subject to frequent transfers; they develop a sense of casual approach to work. As a result, the operational efficiency of the undertaking suffers a lot.
e) Government Interference:
There is an excessive government interference and control organisation in department. These undertakings are not given freedom to decide their own policies. Centralised control leads to delay in action. Red-tapism and bureaucracy have become the limiting features of these organisations.