The Third Element of Web Development

When learning to code, many new developers start with HTML and CSS. These are the foundations of web development, providing structure and aesthetic vibe respectively. But javascript is the third element that makes everything work. It is a client-side programming language that allows you to make dynamic changes on web pages and apps. It can change fonts, images, text, and form fields in web pages, and it can add interactivity to websites and applications.

Javascript is an interpreted language, meaning that the web browser reads and interprets javascript scripts. The javascript engine then turns the scripts into machine code to be executed in the browser. This process is called compiling. The javascript engine also validates the code for syntax and correctness. It can do this for single-line comments that are preceded by a double forward slash (//), and for multi-line comments that are indented with two spaces. The javascript engine then scans the code for functions and variables to create memory in the browser and set them up on the call stack. When the function is called, the javascript engine will then run through the code line by line. As it runs through the code, it will check each variable and function for an initial value. If the code does not set a value for a variable, then it will store that variable as undefined in the memory.

As it runs through the code, javascript will perform math functions on data, like adding, subtracting, multiplying and dividing. It will also do string operations, such as concatenation and substitution. It can also do logical operations, such as comparisons. It can also use arrays, which are groups of elements that can grow or shrink at will. Finally, javascript can also use a function that is similar to an eval statement that allows you to execute statements that are passed to it as strings.

There are several factors that affect the performance of javascript in a browser, such as frequent interaction with the Document Object Model (DOM), which slows down rendering. There are ways to enhance the performance of javascript such as batching DOM updates and minimizing function calls.

Javascript is a popular programming language that can be used in both client-side and server-side programs. It is relatively simple to learn, has a small footprint, and is fast. It also has a large community of resources for beginners to learn more about the language. In addition, it is versatile and can be used in a variety of environments, including desktop computers and mobile devices.