Symmetric vs Asymmetric Encryption

Context

Encryption is a core computer science and security concept that appears in backend systems, networking, and application design. Interviewers ask this to test whether you understand how secure communication is established in practice.

Question

Explain the difference between symmetric and asymmetric encryption.

Your answer should cover:

1. How keys are used in each model
2. Why one approach is typically faster than the other
3. When each method is preferred in real systems
4. How both are often combined in protocols such as HTTPS

Scope Guidance

You do not need to derive cryptographic math or prove security properties. A strong answer should clearly compare the two approaches, describe their trade-offs, and give at least one practical example of how they work together in production systems.