Vasudev is one hundred percent correct on all counts. CTC may, and normally does, include all expenditure that the employer incurs on behalf of the employee. Though different companies include different elements in the calculation of CTC, and though you will never find it clearly defined anywhere, CTC normally includes elements that are paid to the employee by way of salary and various allowances, AND also other expenses the employer incurs on behalf of the employee to comply with various legal provisions. Some typical examples are: Employer's contribution towards Provident Fund, Gratuity, Leave Encashment (unfair, but many companies do it), Mediclaim premium, Group Insurance premium, estimated annual bonus, etc.
As some members have already pointed out, many of us confuse CTC with pay and allowances, and hence feel that all the amounts mentioned in the breakup of the CTC are payable to the employee directly. However, this is not the case, as already explained by many.