# Asynchronous vs Synchronous execution ###### tags: `C basics` #### 整理:BY.Y, 2021/06/29 #### src: >1. https://stackoverflow.com/questions/748175/asynchronous-vs-synchronous-execution-what-does-it-really-mean 根據stack overflow上的回應: >Synchronous/Asynchronous HAS NOTHING TO DO WITH MULTI-THREADING. synchronous強調的是,工作**順序的關係**,不管是single-thread或者multi-thread 舉個生活上常見的例子: >我一定先刷完牙,才吃午餐。 >刷牙-->吃午餐 >是一種順序上的關係 如果扯到single-thread 和 multi-thread,畫成圖會長成這樣: ***以下源自stack overflow上的回應*** Synchronous (one thread): ![](https://i.imgur.com/8KVHh11.png) Synchronous (multi-threaded): ![](https://i.imgur.com/KOa8BQp.png) Asynchronous (one thread): ![](https://i.imgur.com/vHmgAjw.png) Asynchronous (multi-Threaded): ![](https://i.imgur.com/HM1rnHG.png)