What is the key difference between 'paying income tax' and 'filing income tax returns'?

Which ITR form is suitable for an individual who earns income from salary, interest, rental income from one house property, and has capital gains from investments?

What is the primary advantage of using ITR 4 for taxpayers engaged in business?

What is the due date for filing income tax returns for individuals who are not required to undergo an audit?

What is the penalty for failing to file income tax returns by the due date?