What is the taxability for income earned by NRIs?

For NRIs only the income which is earned or accrued in India will be taxable in India. So, any income which is earned by an NRI outside India will not be taxable in India.

Examples of Taxable Incomes:
-Professional fees received in India
-Capital Gains on transfer of assets situated in India
-Interest Income on fixed deposits or savings bank account in India

Examples of Non Taxable Incomes:
-Salary Income abroad
-Interest earned on NRE account