The Basics of Javascript

When learning how to program, most developers start with HTML and CSS. Once they have the structure and aesthetic of their site or project established, they look to javascript. This is the magic element that makes your website dynamic and allows you to do cool things like validate forms, create visual effects, and update content in real time.

The basics of javascript are simple enough to understand. It is a scripting language that runs in a host environment, typically a web browser. Its event-driven nature means that it can respond to events such as keyboard input or mouse clicks on a page, and its access to the Document Object Model (DOM) allows it to manipulate the fonts, images, text, and other elements of a webpage.

There are several types of data in javascript: variables, integers, boolean values, arrays, and objects. Variables are containers that can hold any type of value. They can be assigned a name (like the example above with the variable named “name”). Unlike some other languages, variables are not assigned an initial value – they can have a default value set. This default value is referred to as undefined. The variables in javascript can be declared using the keywords let, const, or var. The keyword let allows you to declare a variable that is only available within the block in which it is declared. The keyword const, on the other hand, indicates that the variable’s value cannot be changed, and the variable will remain undefined outside of its declaration block.

Other features in javascript include arithmetic operators, string handling functions, and recursion. Logical operators are also present, including and , and they can be combined with the boolean operators to perform more complex logic. There are also bitwise operators that can operate on integers, boolean values, and floats.

Finally, javascript supports comments that are similar to those in other languages. Single-line comments are written after a double forward slash (//), and multi-line comments are used between the strings /* and */.

One of the best parts about javascript is its simplicity. It is easy to read and run, compared to some other scripting languages, and errors are easily spotted and corrected. It is also able to execute code directly in the browser, without connecting to a server or needing to be compiled before running. This is especially true with modern browsers that have a built-in javascript interpreter and compiler.