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Excellent.

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Once we have covered async patterns, we're going to use throughout the course.

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Now let's talk about events in Algiers when working on browser JavaScript apps, a big part of our work

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is to handle events.

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For example, user clicks a button.

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And of course, in our program, we handle that.

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User hovers over the link.

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And again, same deal in our program.

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We are handling that.

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And hopefully you get the gist essentially as our program executes, at least in part, it is controlled

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by events, of course, depending on the program.

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But it's safe to say that in browser app those events are mostly external.

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Now that style of programming is actually called event driven programming.

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And effectively, it's just that a style in which the flow of the program is at least in part, determined

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by the events that occur as the program executes.

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Now, it's easier to imagine that, of course, when you have a GUI, right, the graphical interface,

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just like the button and Linc's example I just mentioned.

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But what about server side?

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Is it also possible?

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And of course, the answer is yes.

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In fact, event driven programming is used heavily in jazz, and in the following videos you'll see

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some of the examples of it.

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And basically the idea is following.

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We listen for specific events and register functions that will execute in response to those events.

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So once our event takes place, hombach function fires just like in our imaginary button example.

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Now, before we continue, let me stress something.

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Our first examples are going to be basic and even somewhat silly.

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But don't let that fool you.

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Many built in modules and Norges do use events under the hood and therefore making events an event driven

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programming a big part of no jayesh.