"As soon as you're connected to the Internet, applications can potentially send whatever they want to wherever they want. Most often they do this to your benefit. But sometimes, like in case of tracking software, trojans or other malware, they don't.
But you don't notice anything, because all of this happens invisibly under the hood."
There’s a lot wrong with this: you could be using the wrong version of code that has exploits, has a bug in it, or worse it could have malware bundled in on purpose—you just don’t know.
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Node.js for example, it includes an extra 600MB of libraries you don’t need.