Salary Break Up

Net salary is the take home salary of the emolyee while gross salary is the figure before making statutory or other deductions.

gross salary is basic+ HRA+ trnasport+ other allowance.

Gross salary minus pf contribution, ESI contribution, professional tax contribution etc. (as per applicability ) becomes net salary.

Basic: 30% of Gross Salary (CTC)

HRA: 50%/60% of Basic

Conveyances- 25% 
Medical- 10% 
Other- 5%.... 

Employers Contribution for PF (12% of Basic) 
Employees Contribution for PF (12% of Basic) 
Employees Contribution for ESIC (1.75% of Gross) 

Employers Contribution for ESIC (4.75% of Gross) 

In CTC, Salary Distribution can be 

(A) Basic Salary + HRA + DA 
(B) Conveyance + Medical + Other / Special Allowance if any 
(C) Employers Contribution for PF (12% of Basic) 
Employers Contribution for ESIC (4.75% of Gross) 
(D) Employees Contribution for PF (12% of Basic) 
Employees Contribution for ESIC (1.75% of Gross) 
Gross Salary = (A) + (B) 
CTC = (A) + (B) + (C) 
Net in Hand = (A) + (B) - (D) ...