JavaScript syntax is the set of rules, how JavaScript programs are constructed: The JavaScript syntax defines two types of values: Fixed values are called Literals. Variable values are called Variables. The two most important syntax rules for fixed values are: 1. Numbers are written with or without decimals: 2.

The getOwnPropertyNames() method returns all properties. The Object.keys() method returns all enumerable properties. If you define object properties without enumerable:false, the two methods will return the same.

Apr 3, 2025 · JavaScript is designed on an object-based paradigm. An object is a collection of properties, and a property is an association between a name (or key) and a value. A property's value can be a function, in which case the property is known as a method.

Mar 7, 2025 · Once you have a firm grasp of the fundamentals, you can use the reference to get more details on individual objects and language constructs. JavaScript standard built-in objects, along with their methods and properties. JavaScript statements and declarations. JavaScript expressions and operators. ?. ?? JavaScript functions. JavaScript classes.

JavaScript borrows most of its syntax from Java, but also inherits from Awk and Perl, with some indirect influence from Self in its object prototype system. JavaScript is case sensitive. It is common to start the name of a constructor with a capitalized letter, and the name of a function or variable with a lower-case letter. Example:

In this article, I want to dig much deeper into the concept of object properties and how they can be used. Properties are like variables: They are declared with a name, and used to contain a piece of data. But while variables usually exist in the global space, a property is declared on an object.

Mar 24, 2025 · In JavaScript, syntax dictates how you structure statements, declarations, and expressions so that your code can be understood and executed properly by the JavaScript engine. A variable is a named container that stores data. In JavaScript, you have three main ways to declare variables.

JavaScript and ReactJS Cheat Sheets is a web application that provides a quick reference guide to the syntax, methods, and properties of JavaScript. It is designed for developers and learners who need a handy and concise resource for common JavaScript tasks, such as manipulating arrays, working with dates, handling errors, and creating classes.

Learn JavaScript syntax with examples to master coding basics. Understand key concepts and write efficient scripts with our easy-to-follow guide.

JavaScript is no longer just a scripting language for browsers — it’s the beating heart of modern web development, backend services, native apps, IoT, and even AI tooling. ... 1. ⚙ Syntax & Keywords (15 Terms) var, let, const. ... Check if property exists or object is instance of constructor. delete. Removes object properties.