核心模块
Node.js 有些模块编译成二进制文件。 这些模块在本文档的其他地方有更详细的描述。
核心模块在 Node.js 源代码中定义，位于 lib/ 文件夹中。
如果将核心模块的标识符传给 require()，则始终优先加载核心模块。
例如，require('http') 将始终返回内置的 HTTP 模块，即使存在该名称的文件。
核心模块也可以使用 node: 前缀来识别，在这种情况下，它会绕过 require 缓存。
例如，require('node:http') 将始终返回内置的 HTTP 模块，即使有该名称的 require.cache 条目。
Node.js has several modules compiled into the binary. These modules are described in greater detail elsewhere in this documentation.
The core modules are defined within the Node.js source and are located in the
lib/ folder.
Core modules are always preferentially loaded if their identifier is
passed to require(). For instance, require('http') will always
return the built in HTTP module, even if there is a file by that name.
Core modules can also be identified using the node: prefix, in which case
it bypasses the require cache. For instance, require('node:http') will
always return the built in HTTP module, even if there is require.cache entry
by that name.