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In this particular video.

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Let's see how the code that we write that is JavaScript get executed in a browser.

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Remember, JavaScript runs in the browser, so how our code gets executed.

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Let's have a look.

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Remember that all browsers has a built in JavaScript engine.

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And all these engines differ based on the browser.

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First for Chrome, we have JavaScript engine called V8 engine.

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For Firefox or Mozilla.

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The engine is called Spider Monkey and Internet Explorer.

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It also used what is called Chikara Opera or Presto, but this one is deprecated.

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So for our purposes, we are going to use the JavaScript engine that is built in into Chrome.

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So let's see how our code get executed.

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First, remember that JavaScript engine is a computer program that runs JavaScript code.

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And again, computers only understand machine code, which means that the code that we write, it always

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converts into zeros and ones.

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This is what our computers understand.

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So all the code that we write when compiling it convert into zeros and one using V8 engine.

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Now let's look at the steps involved when executing our code using V8 engine to machine code.

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So let's say that this is our source code.

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Source code represents the code that we have written.

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So before it can get executed its path through some process.

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So from source code, it will now change to what is called a AST and that is abstract syntax tree.

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And this is what you call parser.

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Meaning our code will not pass from source code to a different format called AST, which represents

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abstract syntax tree.

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Then from HD it will also convert to what is called machine code and this what you call compilation

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then.

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So machine code is a code that executed by the computer.

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Then from there, our browser now takes that, and then that process is what we call interpreter.

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Now the user sees what we have rendered.

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So this is the basic flow, how our code is get executed.

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If we want to learn more about this, you can read resources to enhance your knowledge about how code

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is being executed.