Concurrency vs Parallelism

Introduction

以感情關係解釋：

• Concurrency：2017年，你和兩個女孩交往，腳踏兩條船，為了同時維繫多個感情關係，必須時常在不同的感情中切換

• Parallelism：2017年，你和兩個女孩交往，你很專情但最後都分手了，而一段在夏天、另一段在冬天。

Example

• Nodejs event loop is about concurrency, as it is single-thread, but have non-blocking IO, can process different jobs at the same time - Concurrency

• For Multi-thread with multiple CPU core, each thread can process the job at the same time - Parallel

Reference

Concurrency與Parallelism的不同之處Medium