Dear Mahesh, do not rely on someone else's explanations and definitions. Make your own interpretation. Please purchase only the Bare Acts of the Factories Act, Payment of Bonus Act, Payment of Wages Act, Payment of Gratuity Act, Minimum Wages Act, Interstate Migrant Workmen's Act, Contract Labour Act, PF Act, ESI Act, and the concerned Rules. In the Act, you can find the details of statutory obligations, and in the Rules, you will get all the forms and formats of Returns, Reports, and Registers.
While asking for Acts and Rules in the Law Book Stores or in the Government Press, specifically ask for Karnataka State or Central, whichever is applicable to you. All the best.