Concurrency vs Parallelism: What's the Real Difference and When to Use Each? Alternatively, if you prefer a

Parallelism is like a team of workers building a house together. Concurrency is a single worker switching between tasks (foundation, walls, roof) but not actually doing them simultaneously.

For web servers:
- Concurrency: Node.js (event loop).
- Parallelism: Apache (multi-process).

Tools: `Kubernetes` for scaling parallelism, `Redis` for managing concurrent state.