As per the Income Tax Law, there are different forms of returns prescribed for different taxpayers. The forms applicable for AY 2018-19 (FY 2017-18) are as following: 

 

FORM
APPLICABLE   WHEN YOU HAVE -
ITR-1
Salary/Pension,   One House Property Income, Other Sources (Income shall be less than Rs.50   Lakhs) - Applicable for Resident Indians only from AY 18-19).
ITR-2
Everything   from ITR-1 (or when your income is more than Rs.50 Lakhs), Capital Gains,   Foreign Income, Agriculture Income more than Rs.5000. (Applicable for RNOR   (Resident but Not Ordinarily Resident) and NRIs (Non-Resident Individuals)   also from AY 18-19)
ITR-3
Everything   from ITR-2 + Business/Profession Income (Applicable for Partners having   Income from Partnership Firm from AY 18-19)
ITR-4
Presumptive Business Income under Section 44AD(Deemed Profit 8% or 6%),   Section 44ADA(Deemed Profit 50%), Section 44AE(Deemed Profit-Rs.7500/vehicle   pm) - GSTR No. And Turnover/Gross Receipts details required as per GST Return   filed while filing ITR from AY18-19.
ITR-5
Partnership   Firms, Limited Liability Partnerships (LLPs), AOP’s (Association of Persons),   Artificial Juridical Persons (AJP’s), Body of Individuals (BOI’s) and Local Authorities.
ITR-6
Companies 
ITR-7
Persons/Companies   under Section 139(4A), Section 139(4B), Section 139(4C), Section 139(4D)