How JavaScript Works

JavaScript is a programming language widely used for web development, interactive user interfaces, and server-side applications.

Because JavaScript is fundamental to web development, it's a great choice for building a strong foundation in technology.

JavaScript is also a good choice for beginners because it is easier to learn and has extensive community support.

Consider this code to add two numbers in JavaScript and C++ programming.

As you can see, the JavaScript code is easier to understand and read, while the C++ code is more complicated and needs extra steps.

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How does JavaScript work?

Much like English or German are languages for communicating with people, think of programming as a language for communicating with computers.

In English, we use words and grammar in certain ways to convey meaning. Similarly, JavaScript uses specific syntax and keywords to instruct a computer on what actions to perform.

Once you understand the basic keywords and how to use them, you can write instructions that enable a computer to solve different problems.

As you might have noticed, the code in JavaScript and C++ is different. JavaScript is simpler and more straightforward, while C++ requires more detailed instructions for the same task.

So, why do JavaScript and C++ require different code to perform the same task (like adding two numbers)?

Computers do not directly understand the code you write.

When you write and run code, JavaScript uses an interpreter and just-in-time (JIT) compiler to convert your code into machine code that the computer can understand.

In the case of C++, a compiler is used to convert the code into machine code that the computer understands.

These tools (the JavaScript interpreter and the C++ compiler) function differently, leading to variations in syntax.

Although the syntax of programming languages is different, the basic concepts are the same. So once you learn one language, it becomes easier to learn another.

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JavaScript Engine

As mentioned, the JavaScript engine translates your code into instructions that your computer can understand.

The interpreter works line by line, meaning:

1. The JavaScript interpreter reads the first line of code.
2. It translates the code into machine-readable instructions that your computer can execute.
3. The interpreter then runs the instructions.
4. It moves on to the next line and repeats the process.

Here's a visual representation of how the JavaScript interpreter works:

Now that you have a solid understanding of how JavaScript works, you're ready to embark on your JavaScript journey on Programiz PRO.