The built-in globals in Node.js
Node.js has a number of built-in global identifiers that every Node.js developer should have some familiarity with. Some of these are true globals, being visible everywhere; others exist at the module level, but are inherent to every module, thus being pseudo-globals.
First, let's go through the list of 'true globals':
global- The global namespace. Setting a property to this namespace makes it globally visible within the running process.
process- The Node.js built-in
processmodule, which provides interaction with the current Node.js process. Read More
console- The Node.js built-in
consolemodule, which wraps various STDIO functionality in a browser-like way. Read More
clearInterval()- The built-in timer functions are globals. Read More
As mentioned above, there are also a number of 'pseudo-globals' included at the module level in every module:
exports- These objects all pertain to the Node.js module system. Read More
__filenamekeyword contains the path of the currently executing file. Note that this is not defined while running the Node.js REPL.
__dirnamekeyword contains the path to the root directory of the currently executing script. Also not present in the Node.js REPL.
require()function is a built-in function, exposed per-module, that allows other valid modules to be included. Read More
Much of this functionality can be extremely useful for a Node.js developer's daily life - but at the very least, remember these as bad names to use for your own functions!