Dear Mahesh
Do not go for someones explanation and definitions. You make your own interpretation. Please purchase only Bare Acts of 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 Act you can find the details of statutory obligations and in Rules you will get all the forms and formats of Returns, Reports, Registers.
While asking for Acts and Rules in the Law Book Stores or in Government Press specifically ask for Karnataka State or Central whatever applicable to you.
All the best.