Income tax Slab rates for 2011-2012
India

Upto Rs 1.8 lakh (Rs 1.9 lakh for women/Rs 2.5 lakh for Senior citizen - age 60 to 80/Rs 5 lakh for very senior citizen - aged above 80): Nil
Above 1.8 lakh to Rs 5 lakh : 10 %
Above 5 lakh to Rs 8 lakh : 20 %
Above 8 lakh : 30 %

In addition to this one can save tax on extra Rs 1 lakh amount by making deposits in PF, NSC, LIC, Mutual funds etc.

For more info

Income Tax Dept. >> e-Return filing (31 July is the last date of filing the IT returns)

Salaraied employees who have (no other income) an income less than Rs 5 lakh are exempted for filing the returns.