Hi Venky
Gross is sum of basic, HRA, conveyance allowance, medical reimbursement, education allowance and DA.
CTC is cost to the company i.e. it includes gross and statutory deductions like PF, ESI, Bonus, PT.
For Ex. an employee is CTC is Rs.3,20,000/- (which includes gross and statutory deductions)
then his take home salary would be approx. Rs.24,000/- (after deducting statutory deductions)
Hope this will help you.
Regards
Sudha