What exactly does "asynchronous" mean?

Hey everyone!

I am currently taking the Node.js course here on Codecademy, and I have a question.

I got to the Asynchronous JavaScript with Node.js part, and it says something like this:

In server-side development, we often perform time-consuming tasks such as reading files or querying a database. Instead of halting the execution of our code to await these operations or using multiple threads like other back end environments, Node was designed to use an event loop like the one used in browser-based JavaScript execution. The event-loop enables asynchronous actions to be handled in a non-blocking way.

But I don’t understand. I have always thought that “asynchronous” tasks are those that execute at the same time. Therefore, you’d need multiple threads in order to do any kind of asynchronous stuff. But here they’re telling me that Node doesn’t use multiple threads, yet it manages to handle asynchronous actions. Which must mean that “asynchronous tasks” aren’t what I think.

So…could someone please explain to me what asynchronous tasks really are? I would really appreciate it :pleading_face:

Hello @yizuhi. I think asynchronous means one at a time, or not synchronised. (Coming from the prefix a meaning not, I believe.)

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Thank you so much for the article, it really helped clear my mind. (Also knowing I’m not the only one with that question really comforts me :sweat_smile:).

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