Getting Started With JavaScript
When you click a button on a website, you’re interacting with a combination of HTML, CSS and JavaScript. These are the languages that allow you to send and receive data with a server, validate forms, create visual effects, etc. All of this work happens thanks to a process called dynamically updating content, and JavaScript is at the heart of it.
When compared with other programming languages, javascript is relatively lightweight. This means that it doesn’t put too much strain on your CPU or RAM, and this can help improve your performance. JS is also an object-oriented language, which means that it allows you to build more complex applications.
Another reason why javascript is so popular is that it provides a variety of built-in functions that can be used to make web pages and applications more interactive. These include DOM manipulation, object lifecycle methods, and event handling techniques. In addition, javascript offers features like object inheritance and class abstraction that allow developers to design more complex applications.
Aside from its many built-in functions, javascript is also a very flexible language. It can be compiled and interpreted, and it supports multiple platforms. The interpreted version of the language is used by modern browsers, while the compiled versions are used for desktop apps and mobile devices.
To get started with javascript, you’ll need to install a modern browser. Firefox, Chrome and Safari all support javascript, and they all have built-in consoles that enable you to enter javascript code and run it immediately in the browser. You can open the console by clicking the menu (the three dots in the top right corner of the window) and selecting More Tools > Developer Tools. Alternatively, you can press Control+Shift+J (Windows) or Command+Shift+J (Mac).
Once the browser has loaded the javascript file, it runs it in a special engine called the Global execution context. This engine uses a Call Stack, a LIFO data structure that manages function calls. Each time a function is called, a new Stack Frame is pushed onto the Call Stack. This contains information about the function’s arguments, local variables and its return address. Once the function returns, its Stack Frame is popped off of the Call Stack and execution continues from the return address.
There are several optimizations that the javascript engine performs on your code to improve performance and speed. One such technique is inlining, where the javascript engine inserts the actual code for a function call into the location where it was invoked. For example, if you have a function that is called multiple times, the engine will replace the original call with the return value of the function.
JavaScript also includes a number of other features that can improve developer productivity, including string and number casting, inlining, and object invocation.