The event loop is a core programming concept that coordinates task execution with asynchronous event handling. Widely found in: JavaScript, Node.js, Browser runtimes, Flutter, java, Game engines and some high-performance services such as Redis and Nginx The advantages of a normal synchronous design are linearity and simplicity, but the disadvantage is that the entire program execution can easily get stuck on some time-consuming operations. console . log ( 1 ); readSomeFiles (); // time-consuming operations console . log ( 2 ); Enter fullscreen mode Exit fullscreen mode the CPU spends most of its time waiting for I/O threads are blocked concurrency is poor So, in order to better utilize the CPU and more rationally allocate timer tasks and simple ordinary tasks, the concept of the event loop was born. Systems that use event loops typically operate like this (Think about how you usually write JavaScript code): console . log ( 1 ); setTimeout (() => console . log ( 2 )); Promise . resolve ().…