Article 120: Language to be used in Parliament—
 Notwithstanding anything in part XVII, but subject to the provisions of article 348, business in Parliament shall be transacted in Hindi or in English:
Provided that the Chairman of the Council of States or Speaker of the House of the People, or person acting as such, as the case may be, may permit any member who cannot adequately express himself in Hindi or in English to address the House in his mother-tongue.
 Unless Parliament by law otherwise provides, this article shall, after the expiration of a period of fifteen years from the commencement of this Constitution, have effect as if the words “or in English” were omitted there from.
Article 210: Language to be used in the Legislature—
 Notwithstanding anything in part XVII, but subject to the provisions of article 348, business in the Legislature of a State shall be transacted in the official language or languages of the State or in Hindi or in English:
Provided that the Speaker of the Legislative Assembly or Chairman of the Legislative Council, or person acting as such, as the case may be, may permit any member who cannot adequately express himself in any of the languages aforesaid to address the House in his mother-tongue.
 Unless the Legislature of the State by law otherwise provides, this article shall, after the expiration of a period of fifteen years from the commencement of this Constitution, have effect as if the words “or in English” were omitted there from:
Provided that in relation to the Legislatures of the States of Himachal Pradesh, Manipur, Meghalaya and Tripura this clause shall have effect as if for the words “fifteen years” occurring therein, the words “twenty-five years” were substituted:
Provided further that in relation to the Legislature of the States of Arunachal Pradesh, Goa and Mizoram, this clause shall have effect as if for the words “fifteen years” occurring therein, the words “forty years” were substituted.
Article 343— Official language of the Union
 The official language of the Union shall be Hindi in Devnagari script. The form of numerals to be used for the official purposes of the Union shall be the international form of Indian numerals.
 Notwithstanding anything in clause (1), for a period of fifteen years from the commencement of this Constitution, the English language shall continue to be used for all the official purposes of the Union for which it was being used immediately before such commencement:
Provided that the President may, during the said period, by order authorise the use of the Hindi language in addition to the English language and of the Devnagari form of numerals in addition to the internationl form of Indian numerals for any of the official purposes of the Union.
 Notwithstanding anything in this article, Parliament may be law provide for the use, after the said period of fifteen years, of— [a] the English language, or [b] the Devnagari form of numerals, for such purposes as may be specified in the law.
Commission and Committee of Parliament on official language-
 The President shall, at the expiration of five years from the commencement of this Constitution and thereafter at the expiration of ten years from such commencement, by order constitute a Commission which shall consist of a Chairman and such other members representing the different languages specified in the Eighth Schedule as the President may appoint, and the order shall define the procedure to be followed by the Commission.
 It shall be the duty of the Commission to make recommendations to the President as to—
[a] the progressive use of the Hindi language for the official purposes of the Union;
[b] restrictions on the use of the English language for all or any of the official purposes of the Union;
[c] the language to be used for all or any of the purposes mentioned in article 348;
[d] the form of numerals to be used for any one or more specified purposes of the Union;
[e] any other matter referred to the Commission by the President as regards the official language of the Union and the language for communication between the Union and a State or between one State and another and their use.
 In making their recommendations under clause (2), the Commission shall have due regard to the industrial, cultural and scientific advancement of India, and the just claims and the interests of persons belonging to the non-Hindi speaking areas in regard to the public services.
 There shall be constituted a Committee consisting of thirty members, of whom twenty shall be members of the House of the People and ten shall be members of the Council of States to be elected respectively by the members of the House of the People and the members of the Council of States in accordance with the system of proportional representation by means of the single transferable vote.
 It shall be the duty of the Committee to examine the recommendations of the Commission constituted under clause (1) and to report to the President their opinion thereon.
 Notwithstanding anything in article 343, the President may, after consideration of the report referred to in clause (5), issue directions in accordance with the whole or any part of that report.
Article 345—Official language or languages of a State-
Subject to the provisions of articles 346 and 347, the legislature of a State may by law adopt any one or more of the languages in use in the State or Hindi as the Language or Languages to be used for all or any of the official purposes of that State:
Provided that, until the Legislature of the State otherwise provides by law, the English language shall continue to be used for those official purposes within the State for which it was being used immediately before the commencement of this Constitution.
Article 346—Official languages for Communication between one State and another or between a State and the Union—
The language for the time being authorised for use in the Union for official purposes shall be the official language for communication between one State and another State and between a State and the Union:
Provided that if two or more States agree that the Hindi language should be the official language for communication between such States, that language may be used for such communication.
Article 347— Special provision relating to language spoken by a section of the population of a State-
On a demand being made in that behalf the President may, if he is satisfied that a substantial proportion of the population of a State desire the use of any language spoken by them to be recognised by that state, direct that such language shall also be officially recognised throughout that State or any part thereof for such purpose as he may specify.
Language of the Supreme Court, High Courts, etc.
Article 348— Language to be used in the Supreme Court and in the High Courts and for Acts, Bills, etc.-
 Notwithstanding anything in the foregoing provisions of this Part, until Parliament by law otherwise provides-
[a] All proceedings in the Supreme Court and in every High Court,
[b] The authoritative texts-
— Of all Bills to be introduced or amendments thereto to be moved in either House of Parliament or in the House or either House of the Legislature of a State;
— Of all Acts passed by Parliament or the Legislature of a State and of all Ordinances promulgated by the President or the Governor of a State, and
— Of all orders, rules, regulations and bye-laws issued under this Constitution or under any law made by Parliament or the Legislature of a State, shall be in the English language.
 The Governor of a State may, with the previous consent of the President, authorise the use of the Hindi language, or any other language used for any official purposes of the State, in proceedings in the High Court having its principal seat in that State:
Provided that nothing in this clause shall apply to any judgment, decree or order passed or made by such High Court.
 Where the Legislature of a State has prescribed any language other than the English language for use in Bills introduced in, or Acts passed by, the Legislature of the State or in Ordinances promulgated by the Governor of the State or in any order, rule, regulation or bye-law referred to in paragraph (iii) of that sub-clause, a translation of the same in the English language published under the authority of the Governor of the State in the Official Gazette of that State shall be deemed to be the authoritative text thereof in the English language under this article.
Article 349— Special procedure for enactment of certain laws relating to language-
During the period of fifteen years from the commencement of this Constitution, no Bill or amendment making provision for the language to be used for any of the purposes mentioned in clause (1) of article 348 shall be introduced or moved in either House of Parliament without the previous sanction of the President, and the President shall not give his sanction to the introduction of any such Bill or the moving of any such amendment except after he has taken into consideration the recommendations of the Commission constituted under clause(1) of article 344 and the report of the Committee constituted under clause(4) of that article.
Language to be used in representations for redress of grievances–
Every person shall be entitled to submit a representation for the redress of any grievance to any officer or authority of the Union or a State in any of the languages used in the Union or in the State, as the case may be.
Facilities for instruction in mother-tongue at the primary stage—
It shall be the endeavor of every State and of every local authority within the State to provide adequate facilities for instruction in the mother-tongue at the primary stage of education to children belonging to linguistic minority groups; and the President may issue such directions to any State as he considers necessary or proper for securing the provision of such facilities.
Special Officer for linguistic minorities—
 There shall be a Special Officer for linguistic minorities to be appointed by the President.
 It shall be the duty of the Special officer to investigate all matters relating to the safeguards provided for linguistic minorities under this Constitution and report to the President upon those matters at such intervals as the President may direct, and the president shall cause all such reports to be laid before each House of Parliament and sent to the Government of the States concerned.
Directive for development of the Hindi language—
It shall be the duty of the Union to promote the spread of the Hindi language, to develop it so that it may serve as a medium of expression for all the elements of the composite culture of India and to secure its enrichment by assimilating without interfering with its genius, the forms, style and expressions used in Hindustani and in the other languages of India specified in the Eighth Schedule, and by drawing, wherever necessary or desirable, for its vocabulary, primarily on Sanskrit and secondarily on other languages.
Official Language Act, 1963
Accordingly, section 3(2) of the Official Languages Act, 1963 (amended in 1967) provides for continuing the use of English in official work even after 25 January 1965.
The Act also lays down that both Hindi and English shall compulsorily be used for certain specified purposes such as Resolutions, General Orders, Rules, Notifications, Administrative and other Reports, Press Communiqués; Administrative and other Reports and Official Papers to be laid before a House or the Houses of Parliament; Contracts, Agreements, Licences, Permits, Tender Notices and Forms of Tender, etc.
In 1976, Official Language Rules were framed under the provisions of section 8(1) of the Official Languages Act, 1963.
Its salient features are as under—
They apply to all Central Government Offices, including any office of a Commission, Committee or Tribunal appointed by the Central Government and Corporation or Company owned or controlled by it;
Communications from a Central Government Office to State/Union Territories or to any person in Region “A” comprising the States of Uttar Pradesh, Uttarakhand, Himachal Pradesh, Madhya Pradesh, Chhattisgarh, Bihar, Jharkhand, Rajasthan, Haryana and UTs of Andaman and Nicobar Islands and Delhi, shall be in Hindi;
Communications from a Central Government Office to States/UTs in Region “B” comprising the States of Punjab, Gujarat, Maharashtra and the Union Territory of Chandigarh, shall ordinarily be in Hindi. However, communication to any person in Region “B” may be either in English or Hindi;
Communications from a Central Government Office to a State Government Office in region ‘C’ comprising all other States and UTs not included in region ‘A’ & ‘B’ or to any office (note being a Central Government Office) or person shall be in English;
Communications between Central Government Offices and from Central Government Offices to the Offices of the State Governments/Union Territories and individuals, etc., will be in Hindi in such proportions as may be determined from time to time;
All Manuals, Codes and other Procedural literature relating to Central Government Offices are required to be prepared both in Hindi and English. All Forms, Headings of Registers, Name Plates, Notice Boards and various items of stationery, etc., are also required to be in Hindi and English;
It shall be the responsibility of the officer signing the documents specified in section 3(3) of the Act to ensure that these are issued both in Hindi and English
Shall be the responsibility of the administrative head of each Central Government Office to ensure that the provisions of the Act, the Rules and directions issued under Sub-Rule-2 are properly complied with and to devise suitable and effective check points for this purpose
In compliance with the Official Language Resolution, 1968, an Annual Programme is prepared by the Department of Official Language in which targets are set for the offices of the Central Government with regard to originating correspondence, telegrams, telex, etc., in Hindi.
A Quarterly Progress Report is called for from the offices of the Central Government regarding achievements vis-à-vis the said targets.
An Annual Assessment Report is prepared on the basis of the Quarterly Progress Reports, which is laid on the Tables of both Houses of the Parliament and copies endorsed to State Governments and the Ministries/Departments of the Central Government.
Eight Regional Implementation Offices have been established at Bangalore, Cochin, Mumbai, Kolkata, Guwahati, Bhopal, Delhi and Ghaziabad to monitor the implementation of Official Language Policy of the Union.
A Committee of Parliament on Official Language was constituted in 1976 under section 4 of the Official Languages Act, 1963 to periodically review the progress in the use of Hindi as the Official Language of the Union and to submit a report to the President.
The Committee consists of 20 Members of the Lok Sabha and 10 of the Rajya Sabha.
The Committee have decided to submit its report in parts. It has so far submitted to the President eight parts of its report. The Presidential Orders on seven parts of its report have been issued and work is in progress on the eighth part.
The Kendriya Hindi Samiti was constituted in the year 1967. It is chaired by the Prime Minister. It is the apex policy making body which lays down the guidelines for the propagation and progressive use of Hindi as Official Language of the Union.
Under the directions of the Kendriya Hindi Samiti, Hindi Salahakar Samitis have been constituted in all Ministries/Departments under the chairmanship of the Ministers concerned. These Samitis periodically review the progress in the use of Hindi in their respective Ministries/Departments and the offices/undertakings and suggest measures to promote the use of Hindi.