全局执行上下文是由函数创建的吗？

Question

I was learning JS and execution contexts. Also, I found out that there is a special execution context which is executed by default which is fglobal execution context. The question is "Is global execution context a function which is executed behind the scenes"?

Answer 1

It's not a function, it's an abstraction that holds certain information about the context within which javascript is running. It is set up by the javascript engine before it starts to execute any code so it is created by a "function behind the scenes", but it is not itself a function. In the browser, the globsal execution context will include various functions and objects (like the document object). In node on the server, it will be something different. It is closely related to the global scope, but execution context and scope are not identical. It's quite a complex subject, so you may want to read this for more information: https://codeburst.io/js-demystified-04-execution-context-97dea52c8ac6