JavaScript: Things you must know

Alongside HTML and CSS, JavaScript is one of the core technologies of the World Wide Web. JavaScript and it's libraries/frameworks are used on 98% of websites. If you want to get started developing for the web, you must know JavaScript. Some essential concepts and skills that are important to know in JavaScript are:

1. Syntax: As with learning any programming language, it's important to understand the basic syntax of JavaScript, including variables, data types, operators, loops, and control structures.
2. Functions: Functions are a fundamental building block of JavaScript code, and they are used to group together related code and reuse it. It's important to understand how to define and call functions, as well as how to use function arguments and return values.
3. Objects: Objects are used to store and organise data in JavaScript, and they are a key concept in object-oriented programming. It's important to understand how to create and manipulate objects, as well as how to use object properties and methods.
4. Arrays: Arrays are used to store and manipulate lists of data in JavaScript. It's important to understand how to create and access arrays, as well as how to use array methods such as push, pop, shift, and unshift.
5. DOM Manipulation: The Document Object Model (DOM) is a programming interface for HTML and XML documents, and it's important to know how to use JavaScript to manipulate the DOM. This includes understanding how to select elements, change their styles and attributes, and respond to user events.
6. Asynchronous Programming: JavaScript is a single-threaded language, but it has mechanisms for performing asynchronous tasks, such as making HTTP requests or setting timers. It's important to understand how to use these mechanisms to write asynchronous code.
7. Error Handling: It's important to know how to handle and debug errors in JavaScript code. This includes understanding common error types, such as syntax errors and runtime errors, and using tools such as the debugger and try-catch statements.

There is much more to learn but this should already put you ing good state. Remember the best way to improve your skills is to practice writing code and building projects.