Explain how cryptography ensures security and privacy in these technologies

Cryptography plays a critical role in modern applications such as VPNs, blockchain, and digital payments. Answer all of the following prompts.

Explain how cryptography ensures security and privacy in these technologies.
Discuss the potential threat that quantum computing poses to current cryptographic algorithms and introduce the concept of post-quantum cryptography.
How is cryptography applied in social media and cloud computing to protect user data?
Explore the ethical considerations involved in cryptography, particularly in balancing privacy and security. Are there any risks or dilemmas associated with the widespread use of encryption technologies, and how should these be addressed?
Peer Reply Guidance:
Respond to at least two peers with substantive paragraphs.