Section 2(47) of CGST Act 2017 :"Exempt Supply" means supply of any goods or services or both which attracts nil rate of tax or which may be wholly exempt from tax under section 11, or under section 6 of the Integrated Goods and Services Tax Act, and includes non-taxable supply.

Section 2(48) of CGST Act 2017 :"Existing Law" means any law, notification, order, rule or regulation relating to levy and collection of duty or tax on goods or services or both passed or made before the commencement of this Act by Parliament or any Authority or person having the power to make such law, notification, order, rule or regulation.

Section 2(43) of CGST Act 2017 :"Electronic Cash Ledger" means the electronic cash ledger referred to in subsection (1) of section 49.

Section 2(44) of CGST Act 2017 :"Electronic Commerce" means the supply of goods or services or both,
including digital products over digital or electronic network.

Section 2(45) of CGST Act 2017 :"Electronic Commerce Operator" means any person who owns, operates or
manages digital or electronic facility or platform for electronic commerce.

Section 2(46) of CGST Act 2017 :"Electronic Credit Ledger" the electronic credit ledger referred to in sub-section (2) of section 49.

ACCOUNTS AND RECORDS

                                                                        MIGRATION

FAQ ON TRANSITION

FAQ ON UTGST AND OTHERS

FAQ ON RETURNS

FAQ ON SUPPLY

EXPORTS, REFUNDS, DRAWBACKS ETC

IGST, GST COMPENSATION CESS ETC

IMPORTS AND INPUT TAX CREDIT

IMPORTANT FACTS ABOUT TAX INVOICE

FREQUENTLY ASKED QUESTIONS

COMPOSITION SCHEME

Section 2(39) of CGST Act 2017 :"Deemed Exports" means such supplies of goods as may be notified under section 147.

Section 2(40) of CGST Act 2017 :"Designated Authority" means such authority as may be notified by the Board.

Section 2(41) of CGST Act 2017 :"Document" includes written or printed record of any sort and electronic record as defined in clause (t) of section 2 of the Information Technology Act, 2000.

Section 2(42) of CGST Act 2017 :"Drawback" in relation to any goods manufactured in India and exported, means the rebate of duty, tax or cess chargeable on any imported inputs or on any
domestic inputs or input services used in the manufacture of such goods.

Section 2(34) of CGST Act 2017 :"Conveyance" includes a vessel, an aircraft and a vehicle.

Section 2(35) of CGST Act 2017 :"Cost Accountant" means a cost accountant as defined in clause (c) of sub-section (1) of section 2 of the Cost and Works Accountants Act, 1959.

Section 2(36) of CGST Act 2017 :"Council" means the Goods and Services Tax Council established under article 279A of the Constitution.

Section 2(37) of CGST Act 2017 :"Credit Note" means a document issued by a registered person under sub-section (1) of section 34.

Section 2(38) of CGST Act 2017 :"Debit Note" means a document issued by a registered person under sub-section (3) of section 34.

Section 2(32) of CGST Act 2017 :"Continuous supply of Goods" means a supply of goods which is provided, or agreed to be provided, continuously or on recurrent basis, under a contract, whether or not by means of a wire, cable, pipeline or other conduit, and for which the supplier invoices the recipient on a regular or periodic basis and includes supply of such goods as the Government may, subject to such conditions, as it may, by notification, specify.

Section 2(33) of CGST Act 2017 :"Continuous supply of Services" means a supply of services which is provided, or agreed to be provided, continuously or on recurrent basis, under a contract, for a period exceeding three months with periodic payment obligations and includes supply of such services as the Government may, subject to such conditions, as it may, by notification, specify.

Section 2(31) of CGST Act 2017 :"Consideration" in relation to the supply of goods or services or both includes––
(a) any payment made or to be made, whether in money or otherwise, in respect of, in response to, or for the inducement of, the supply of goods or services or both, whether by the recipient or by any other person but shall not include any subsidy given by the Central Government or a State Government;
(b) the monetary value of any act or forbearance, in respect of, in response to, or for the inducement of, the supply of goods or services or both, whether by the recipient or by any other person but shall not include any subsidy given by the Central Government or a State Government:
Provided that a deposit given in respect of the supply of goods or services or both shall not be considered as payment made for such supply unless the supplier applies such deposit as consideration for the said supply.

Section 2(30) of CGST Act 2017 :"Composite Supply" means a supply made by a taxable person to a recipient consisting of two or more taxable supplies of goods or services or both, or any combination thereof, which are naturally bundled and supplied in conjunction with each other in the ordinary course of business, one of which is a principal supply.

Illustration -  Where goods are packed and transported with insurance, the supply of goods, packing materials, transport and insurance is a composite supply and supply of goods is a principal supply.

Analysis
As per Sec 66F of Finance Act 1994 (Old Service Tax Act)
(1) Unless otherwise specified, reference to a service (herein referred to as main service) shall not include reference to a service which is used for providing main service. 
(2) Where a service is capable of differential treatment for any purpose based on its description, the most specific description shall be preferred over a more general description. 
(3) Subject to the provisions of sub-section (2), the taxability of a bundled service shall be determined in the following manner, namely:– 
(a) if various elements of such service are naturally bundled in the ordinary course of business, it shall be treated as provision of the single service which gives such bundle its essential character. For Example- Hotel Accommodation with Breakfast, food etc, Education with Meal and Accommodation.
(b) if various elements of such service are not naturally bundled in the ordinary course of business, it shall be treated as provision of the single service which results in highest liability of service tax.
For Example- A building which is used for commercial purpose on ground floor and for residential purpose on above floors. 
Explanation - For the purposes of sub-section (3), the expression "bundled service" means a bundle of provision of various services wherein an element of provision of one service is combined with an element or elements of provision of any other service or services.
Now as per Sec 2(30) of CGST Act 2017 composite supply consist of goods or services or both which are naturally bundled.

Section 2(25) of CGST Act 2017 :"Commissioner in the Board" means the Commissioner referred to in section 168.

Section 2(26) of CGST Act 2017 :"Common Portal" means the common goods and services tax electronic portal referred to in section 146.

Section 2(27) of CGST Act 2017 :"Common Working Days" in respect of a state or Union territory shall mean such days in succession which are not declared as gazetted holidays by the
Central Government or the concerned State or Union territory Government.

Section 2(28) of CGST Act 2017 :"Company Secretary" means company secretary as defined in clause (c) of sub-section (1) of section 2 of the Company Secretaries Act, 1980.

Section 2(29) of CGST Act 2017 :"Competent Authority" means such authority as may notified by the Government.

Section 2(21) of CGST Act 2017 :"Central Tax" means the central goods and services tax levied under section 9.

Section 2(22) of CGST Act 2017 :"Cess" shall have the same meaning as assigned to it in the Goods and Services Tax (Compensation to States) Act. 

Section 2(23) of CGST Act 2017 :"Chartered Accountant" means a chartered accountant as defined in clause (b) of sub-section (1) of section 2 of the Chartered Accountants Act, 1949.

Section 2(24) of CGST Act 2017 :"Commissioner" means the Commissioner of central tax and includes the Principal Commissioner of central tax appointed under section 3 and the
Commissioner of integrated tax appointed under the Integrated Goods and Services Tax Act.

Section 2(20) of CGST Act 2017 :"Casual Taxable Person" means person who occasionally undertakes transactions involving supply of goods or services or both in the course or furtherance of business, whether as principal, agent or in any other capacity, in a State or a Union territory where he has no fixed place of business.

Section 2(19) of CGST Act 2017 :"Capital Goods" means the goods, the value of which is capitalised in the books of account of the person claiming the input tax credit and which are used or intended to be used in the course or furtherance of business.   

Revising Sections Posted Till Date
Section 1      - Short Title, Extent and Commencement
Section 2(1) - Actionable Claims
Section 2(2) - Address of Delivery
Section 2(3) - Address on Record
Section 2(4) - Adjudicating Authority
Section 2(5) - Agent
Section 2(6) - Aggregate Turnover
Section 2(7) - Agriculturist
Section 2(8) - Appellate Authority
Section 2(9) - Appellate Tribunal
Section 2(10) - Appointed Day
Section 2(11) - Assessment
Section 2(12) - Associated Enterprises
Section 2(13) - Audit
Section 2(14) - Authorised Bank
Section 2(15) - Authorised Representative
Section 2(16) - Board
Section 2(17) - Business
Section 2(18) - Business Vertical

Section 2(18) of CGST Act 2017 :"Business Vertical" means a distinguishable component of an enterprise that is engaged in the supply of individual goods or services or a group of related goods or services which is subject to risks and returns that are different from those of the other business verticals.
Example - Reliance Retail has the following Business Vertical:
a) Reliance Fresh
b) Reliance Digital
c) Reliance LYF
d) Reliance Jewels
e) Reliance Time Out
f) Reliance Market
g) Reliance Trends, Reliance Footprints and Reliance Living

Explanation––For the purposes of this clause, factors that should be considered in determining whether goods or services are related include––
(a) the nature of the goods or services.
(b) the nature of the production processes.
(c) the type or class of customers for the goods or services.
(d) the methods used to distribute the goods or supply of services and
(e) the nature of regulatory environment (wherever applicable), including banking, insurance, or public utilities.

Section 2(17) of CGST Act 2017 :"Business" includes -
(a) any trade, commerce, manufacture, profession, vocation, adventure, wager or any other similar activity, whether or not it is for a pecuniary benefit;
(b) any activity or transaction in connection with or incidental or ancillary to sub-clause (a);
(c) any activity or transaction in the nature of sub-clause (a), whether or not there is volume, frequency, continuity or regularity of such transaction;
(d) supply or acquisition of goods including capital goods and services in connection with commencement or closure of business;
(e) provision by a club, association, society, or any such body (for a subscription or any other consideration) of the facilities or benefits to its members;
(f) admission, for a consideration, of persons to any premises;
(g) services supplied by a person as the holder of an office which has been accepted by him in the course or furtherance of his trade, profession or vocation;
(h) services provided by a race club by way of totalisator or a licence to book maker in such club ; and
(i) any activity or transaction undertaken by the Central Government, a State Government or any local authority in which they are engaged as public authorities.

Analysis - Pecuniary benefit means money is involved, so if money is not involved then also it considered as Business as per CGST Act,2017.
Definition of Business is not exhaustive.
Totalisator means a device showing the number and amount of bets staked on a race, to facilitate the division of the total among those backing the winner.
Bookmaker means a person whose job is to take bets (especially on horse races), calculate odds, and pay out winnings or you can say the manager of a betting shop.
Central Government and State Government working as public authorities like the Driving Licence Issuing Authority, Passport Issuing Authority, PAN Card Issuing Authority, Birth/Death Certificate Issuing Authority etc.

Section 2(16) of CGST Act 2017 :"Board" means the Central Board of Excise and Customs constituted under the Central Boards of Revenue Act,1963.

Section 2(13) of CGST Act 2017 :"Audit" - means the examination of records, returns and other documents maintained or furnished by the registered person under this Act or the rules made thereunder or under any other law for the time being in force to verify the correctness of turnover declared, taxes paid, refund claimed and input tax credit availed, and to assess his compliance with the provisions of this Act or the rules made thereunder.

Section 2(12) of CGST Act 2017 :"Associated Enterprises"  shall have the same meaning as assigned to it in section 92A of the Income Tax Act,1961. 

Analysis - Meaning of associated enterprises as per Income Tax Act.[ http://www.incometaxindia.gov.in/Acts/Income-tax%20Act,%201961/2014/102120000000037184.htm]

Section 2(11) of CGST Act 2017 :"Assessment" - means determination of tax liability under this Act and includes self assessment, re-assessment, provisional assessment, summary assessment and best judgement assessment. 

Analysis 
Self Assessment means when the  assessee calculate GST and pay.
Re-Assessment means when the GST is assessed by proper officer which is in excess or short of GST assessed by assessee.
Provisional Assessment means when the assessee pays GST on estimation basis due to any reason and pay short or get refund excess at the time of final assessment.
Summary Assessment means when the proper officer issue an assessment order on the basis of evidence showing a tax liability of a person coming to his notice to protect the interest of revenue.  

Section 2(8) of CGST Act 2017 :"Appellate Authority" -means an authority appointed or authorised to hear appeals and referred to in section 107.

Section 2(9) of CGST Act 2017 :"Appellate Tribunal" - means the Goods and Service Tax Appellate Tribunal constituted under section 109. 

Section 2(10) of CGST Act 2017 :"Appointed Day" - means the date on which the provisions of this Act shall come into force.

Section 2(7) of CGST Act 2017 :"Agriculturist" - means and Individual or a Hindu Undivided Family who undertakes cultivation of land -
a) by own labour, or 
b) by the labour of family, or
c) by servants on wages payable in cash or kind or by hired labour under personal supervision or the personal supervision of any member of the family.

Section 2(6) of CGST Act 2017 : "Aggregate Turnover" - means
the aggregate value of all taxable supplies (excluding the value of inward supplies on which tax is payable by a person on reverse charge basis), exempt supplies, exports of goods or services or both and inter-State supplies of a person having the same Permanent Account Number, to be computed on all India basis and excludes central tax, State tax, Union territory tax, integrated tax and cess.

Analysis - Aggregate Turnover = 
      Taxable Supplies            
 +   Exempt Supplies
 +   Export of goods or services or both 
 +   Inter- state Supplies of a person having same PAN 
 -    Inward supplies on which tax is payable on reverse charge basis (if included then only deduct) 

Section 2(5) of CGST Act 2017 : "Agent" - means a person, including a factor, broker, commission agent, arhatia, del credere agent, an auctioneer or any other mercantile agent, by whatever name called, who carries on the business of supply or receipt of goods or services or both on behalf of another.

Analysis - Definition of agent is illustrative not exhausted.
Del Credere Agent means where the agent acts not only as a salesperson or broker for the principal, but also as a gurantor of credit extended to the buyer. If the buyer is unable to pay bill after the transaction is completed, a del credere agent may become liable for the amount that was unable to be collected.

Section 2(4) of CGST Act 2017 : "Adjudicating Authority" - means any Authority, appointed or authorised to pass any order or decision under this Act, but does not include the Central Board of Excise and Customs, the Revisional Authority, the Authority for Advance Ruling, the Appellate Authority and the Appellate Tribunal.  

Analysis - There are no general powers to term as adjudicating authority. In other words it will help to avoid dual jurisdictional control now adjudicating officer will be appointed to issue order under the both act i.e. CGST or SGST or UGST.     

As per Central Excise Act, 1944 (Old) - Any authority competent to pass any order or decision under this Act, but does not include the Central Board of Excise and Customs constituted under the Central Boards of Revenue Act, 1963 (54 of 1963), Commissioner of Central Excise (Appeals) or Appellate Tribunal.

As per Service Tax (Old) - Same definition as per Central Excise Act, 1944.

Section 2(3) of CGST Act 2017 : "Address on Record" - The term Address of Delivery means the address of recipient of goods or services or both indicated on tax invoice issued by the registered person for delivery of such goods or services or both. 
In Old Act there is no definition of Address on Record.

Section 2(2) of CGST Act 2017 : "Address of Delivery"- Unless the context otherwise requires, the term "address of delivery" means the address of recipient of goods or services or both indicated on the tax invoice issued by a registered person for delivery of such goods or services or both.

As per Service Tax (Old Act): There is no definition.

Section 2 of CGST Act 2017  : "Definitions" 

Section 2(1) of CGST Act 2017 : Actionable Claim - Actionable Claim means a claim to any debt, other than debt  secured by mortgage of immovable property or by hypothecation or pledge of movable property or to any beneficial interest in movable property not in the possession, either actual or constructive, of the claimant, which the civil court recognise  as affording grounds for relief, whether such debt or beneficial interest be existent, accruing, conditional or contingent (As per Transfer of Property Act,1882).  
Example: Unsecured Claim/ Loan, Pending Litigations, Arrears of Rent, Insurance Claim, Lottery Ticket (Neither Goods nor service as per Sikkim High Court 2013 Judgement), Promo Code.

As per Service Tax (Old Act): Actionable Claim is not service.