Cryptography protects information using mathematical techniques such as encryption, hashing and digital signatures. MCA students should understand the purpose and correct use of these mechanisms rather than treating them as just formulas. A good MCA study plan should leave time for both the theory behind cryptography and regular implementation practice. This point is specifically relevant to the cryptography aspect of MCA study. For this specific question about cryptography, the practical takeaway is to relate the concept to your own MCA learning goal.