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This is the section that I'm waiting for, and that is synchronous versus asynchronous programming.

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After we've gone through this section, it will help us to write fast, good performance code.

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And above all, it will help us to develop real world applications like news app, text to speech application,

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translation app and many more using external APIs.

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So let's get started.

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So in this particular video, we would differentiate differences between synchronous versus asynchronous

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programming.

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Let's see the differences between synchronous versus asynchronous programming.

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Well, synchronous code is executed in a linear fashion.

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That means one line at a time.

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But for asynchronous programming or code, on the other hand, it execute code out of order, meaning

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in power.

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Which means that until this point, all the code that you have been reading are all synchronous code

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because it execute one after the other.

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And if you remember, on the high level of JavaScript, we talk about JavaScript as a single threaded

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programming language.

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That is why a code is being executed in order.

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So if one code takes, let's say, 10 minutes to execute the other code below, it will wait until it

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finished.

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So this is what you call blocking or single threaded.

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So when you say synchronize is also same as what?

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Blocking code.

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But asynchronous programming, on the other hand, don't do that.

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But instead it can execute code in power or concurrently.

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So why is it so?

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And this is a time I will show you why we have this kind of features in JavaScript as asynchronous code.

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So.

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Here comes the question you may be asking that, well, if JavaScript is a single threaded and one thread

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manages or the code is running, why is it that we can run code in power?

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So as you move on you will see the differences.

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So let's say in details, differences between these two programming style.

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Well, we often shorthand asynchronous as async.

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So when I say async, I mean asynchronous or right.

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So for synchronous programming, it is what you call single threaded, meaning it uses one thread to

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manage all our code execution, but for asynchronous code it is also called multithreaded, meaning

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we have more than one thread to manage code execution.

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So why is it so?

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By default JavaScript is a single thread, so I'll prove to you as you move on.

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And again, synchronous code is also called code blocking because if a function or code takes some time

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to run and if otherwise below it cannot run, it means that it's blocking the other code from running.

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But for asynchronous code it is non blocking code.

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As you saw on the high level of JavaScript, we talk about JavaScript as non blocking.

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Right.

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And I showed you how I used that timeout to make this happen again.

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We will revisit this technique again for synchronous code.

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It handle one request at a time.

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When you say requests, it simply means that getting or requesting a certain data from certain API into

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your application.

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In that case, you're going to hand it down one one at a time.

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But for asynchronous, it handled multiple requests at a time.

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And again, synchronous code gives poor user experience whilst asynchronous improve user experience.

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This means how fast your application loads or run.

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So with these two programming techniques, one can affect what user experience because it's slow and

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the other one increase or improve user experience because it runs fast, because code doesn't block

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other code from running again.

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Let's see more in details.

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Let's talk about synchronous programming.

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All right.

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So in this video, let's start with synchronous programming in more details.