Hi Sweta,
Typically, there are three components: Fixed salary, Variable salary, and benefits.
Fixed includes Basic, DA, HRA, PF, PT, SA (This includes earnings as well as deductions).
Variable includes Special allowance, Project allowances, Bonus, Performance pay, Incentive, etc.
The benefits part includes car plan, Holiday package, Leased accommodation, Telephone, Medical/Hospitalization schemes, etc.
All these components together form the CTC.
Regarding Taxable and Non-Taxable components, Sodexo and some medical allowances are considered non-taxable. Most other allowances are either covered under the Income Tax Act or the FBT act.
Therefore, it is advisable to check the FBT act before making any alterations to your current salary structure.