system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What is a thread in programming?

As a second-semester computer science student and 5-year programmer, I'm ashamed to say I don't have a firm idea of what a thread is. I understand certain ideas, like if a method has an event listener, that "thread" will stay open until the listener is deleted. But I don't really understand what a thread *is*. Can somebody please enlighten me?
gpt
Imagine every thread being a worker under you, that has an individual timetable. A normal program gives you one worker by default, doing the stuff the source code wants it to. Each thread you open "hires" another one, where you can assign work to it, splitting some calculations you need basically at the same time, for better work efficiency (for large projects you might even want to hire and fire multiple workers over the course of the project).