A red coding textbook that says “JavaScript for Web Designers.” JavaScript Terms You Must Familiarize Yourself With

JavaScript Coding Terms You Need to Know in 2023

As a JavaScript developer, there are specific JavaScript terms you must familiarize yourself with. These are terms that make up the JavaScript system and are necessary to work as a developer in the field. Not knowing these fundamental terms can pose a potential problem when writing codes or creating applications. 

This article will teach the JavaScript terms you must familiarize yourself with for various experience levels, from beginner to advanced. You will also learn other coding terms that are relevant to your career from time to time. At the end of this article, you will be familiar with applicable terms and be prepared to have a fulfilling developer career.

What Is JavaScript?

JavaScript is a dynamic, text-based programming language that is used to build web pages, web applications, and game applications, among other things. It can be used in both front end and backend development to make websites more interactive by engaging the user. JavaScript is popular for its unique web development style that can be seen on popular platforms like Twitter.

How to Learn JavaScript

You can learn JavaScript through different mediums including coding bootcamps, college degree programs, online courses, and other online resources. Each of these mediums has its own unique advantage which will be discussed further below.

Coding Bootcamps

Coding bootcamps are fast-paced, immersive training programs explicitly designed to equip students with the relevant knowledge and skills required to start a career in technology. Coding bootcamps typically offer several programming languages as courses for students to become highly skilled, including JavaScript.

You can attend a coding bootcamp to learn JavaScript and know that you will be getting the best learning resources to become an expert in the field. This is because coding bootcamps utilize hands-on experience to instill knowledge in students to prepare them for real-life jobs.

Online Courses

There are numerous online web development courses that offer JavaScript training. These courses are typically self-paced and often free making them available to anyone willing to learn. As a beginner, you will find many of these courses useful especially because you get to learn at your own speed and on your own time. 

Degree Programs

You can also go to college and earn credit hours in computer science, computer programming, or any other related field to gain knowledge in JavaScript. The advantage of attending college is the access to a more in-depth curriculum that covers different areas outside of JavaScript, making it easy for students to learn other topics before eventually deciding on their focus.

Free Coding Resources

You also can find a large number of resources available on the internet for free that can help you learn JavaScript. There are articles, tutorials, books, publications, libraries, and online resources like StackOverflow that you can use to your advantage and gain the knowledge you need to start a career as a JavaScript developer. However, this method will require a lot of personal effort, as you will have to spend time searching for all of the information you need.

How to Expand Your JavaScript Vocabulary

Regardless of your level as a developer, you will need to keep expanding your vocabulary to keep up with the industry’s growth and to stay updated on additional terms that arise. It will also help you improve your skill level. Below, you can find some tips that will help you expand your JavaScript vocabulary and stay ahead of your peers.

  1. Familiarize yourself with JavaScript libraries. Every programming language has several libraries that developers can use to their advantage. These libraries will not only help with your code but will also teach you new terms.
  2. Connect with online communities. Join and stay up-to-date with JavScript online communities as developers often communicate through them. Being a part of these communities can help you pick up new terms regularly.
  3. Read industry and JavaScript articles. Many developers own blogs or work with websites to write programming articles. Getting familiar with some of these blogs and reading them regularly will help you learn new terms that are beyond your vocabulary.
  4. Read relevant books. Just as there are articles, there are also JavaScript books and guides that include in-depth information on JavaScript practices and relevant information like terminology. You can read these books to improve your JavaScript knowledge and also broaden your vocabulary.
  5. Practice. When you keep working to improve your skills, you will come across additional terms regularly and also increase your JavaScript vocabulary at the same time.

JavaScript Terms That Beginners Should Know

A smartphone on top of two books with the titles “Stunning CSS” and “JavaScript & jQuery”, respectively. JavaScript Terms You Must Familiarize Yourself With
JavaScript is a fundamental coding language and is important for any programmer to know.


In JavaScript, a Boolean data type has two options: true or false. It is used as a function to return the true or false value of a variable, object, or condition. Every programming language has a data type that only has two values, and JavaScript’s data type is Boolean.


Conditional statements are the primary tool in JavaScript for controlling behavior and making logical decisions on courses of action. There are different conditionals in JavaScript, including “If statements,” “Else statements,” and “Else If statements.”


A JavaScript function is a group of statements or lines of code that perform specific tasks or calculates and determines values. Functions should take some input and return an output where the input and output have a clear relationship. A function is performed when something calls it.


Git is an open-source version control system that tracks content. It allows for communication between a remote, server-based repository and a local repository stored on a developer’s computer. It is the most commonly used version control system. It encourages collaboration and allows multiple developers to make changes to a file.

Keyword/Reserved Word

Keywords are reserved words that are part of the programming language’s syntax. Reserved words are words that cannot be used as identifiers because the language has reserved them. Examples of reserved words in JavaScript are abstract, arguments, boolean, debugger, synchronized, and transient. 


In JavaScript, an object is a self-contained entity with properties and types that define its characteristics. The properties in objects are called keys and the keys are assigned to values. Objects allow you to build complex but simple data structures.


An operator can manipulate or control a specific value or operand. An operand is a quantity or piece of data being operated on. Operators use operands to perform specific mathematical and logical computations. In JavaScript, operators are used to compare values and perform arithmetic operations.

Values and Types

Variables in JavaScript can hold values of any type without any enforcement because JavaScript is dynamically typed. It has typed values but no typed variables because variables in programming languages can contain any data.


VAR is a statement used to represent a variable. Variables are used for storing data and information. When a VAR declares a variable, it becomes empty and has no value. VAR statements are used in JavaScript because they allow you to hide variables of the same name. It is a coding best practice to always use VAR when necessary.


In JavaScript, statements are used to control the program flow. Statements are designed to function independently of any JavaScript object. Statements are composed of values, operators, expressions, keywords, and comments.

Intermediate JavaScript Terms

As an intermediate JavaScript developer, you need to continue equipping yourself with more knowledge to become an expert and write efficient code that can be understood, used, and maintained by others. Below are a few fundamental terms that are necessary for your growth.


An array is a single variable or an ordered list of values that can be used to store various elements. Each value is referred to as an element and is identified by an index. It is frequently used to store lists of elements and access them using a single variable.


A callback is a function that is passed as an argument to another function, which means that it is only executed after another function has completed its execution. Callbacks are useful when you want to execute a function immediately after another function returns.


A closure is a bundled function that has references to its surrounding state. In JavaScript, a closure is created simultaneously as a function. They are the primary method for enabling data privacy, as the enclosed variables are only visible within the containing function. This makes the protected data only accessible from an outside scope through the object’s privileged methods.


Coercion, also known as type coercion, is the process of converting a value from one data type to another automatically. The conversion could be a number, a string, or a Boolean expression.

Config Files

Config files enable developers to configure their applications in an XML block rather than hard-coding values into their scripts. The configuration block may contain strings, numbers, arrays, and HTML. They are used to configure the parameters and initial settings of some computer programs.


A handler is a JavaScript function specializing in a specific type of data or focusing on a particular set of tasks. There are three different handlers, namely event handler, file input handler, and memory handler, each performing their own unique tasks.


In JavaScript, hoisting is a process that occurs during the creating phase of execution. The process allows the interpreter to move all declarations of functions, variables, or classes to the top of the scope before the code is executed. Before the declaration, the functions can be safely used in code.


The inequality operator tests whether or not its two operands are different and returns a Boolean result. It tries to convert and evaluate operands of various types instead of the strict inequality operator, however, JavaScript string values can also contrast inequality.


Prototypes allow you to define strategies applicable to all unique object cases easily. If you refer to a property on an object, JavaScript will use that object’s prototype reference to discover another object to look for the property if that property no longer exists. When an object is created, the inside prototype reference linkage between that object and its fallback occurs.


A slug is a component of a web address that includes a unique identifier at the end of the URL that is used to identify a resource. It could also be the final component of a new document created under a parent document.

Advanced JavaScript Terms

Two books that say “HTML & CSS” and “JavaScript & jQuery” beside a small cactus in a pot. JavaScript Terms You Must Familiarize Yourself With
JavaScript is widely used because it makes websites more interactive for the user.


In JavaScript, the accumulator is the value that we end up with, that is, the net result of the function. It will either contain the initial value or the previous call’s return value. 

Comparison Operators

JavaScript comparison operators are used in logical statements to determine the equality or difference between variables and values. They compare two values and return a Boolean value. They can be used to make decisions and loops.

Code Comments

JavaScript comments are a meaningful way for a developer to deliver a message by writing notes in your code like information on the code, warnings, or suggestions for code readability by the end-user.


An identifier is a name in JavaScript used for variables, functions, and properties to provide labels for specific loops in a code. Identifiers are case-sensitive and have the same rules in other programming languages.


IIFE, or Immediately Invoked Function Expression, is a JavaScript function that executes as soon as it is defined or created. It is a popular design pattern in JavaScript and can be useful because it does not pollute the global object. It is also a straightforward method of isolating variable declarations.


Loops in JavaScript are used to perform the task of running a block of code based on a condition repeatedly. A loop will continue to run until the specified condition returns false. Loops should be used if the number of iterations is known.

Object Literals

An object literal is a list of name-value pairs, separated by commas, and enclosed in curly braces. The name-values can take the form of properties or functions. Object literals sum up data and package it to reduce the overuse of global variables and avoid problems when combining code.


Destructuring allows values or data from arrays, or properties from objects, to be separated and then assigned to separate variables. It can extract multiple properties in a single statement, analyze properties from embedded objects, and set a default value if a property does not exist.

Switch Statements

The switch statement is a type of conditional statement in JavaScript used to perform different actions based on various conditions. It is used to evaluate an expression, match the value of the expression to a case clause, and execute statements associated with the case and cases that follow the matching case. It is frequently used in conjunction with a break or a default keyword.

Truthy and Falsy

Truthy and falsy expressions in JavaScript are not limited to Boolean data types like other programming languages. Truthy values have a Boolean true value, while falsy values have a Boolean false value. While JavaScript has six falsy expressions, any expression that is not one of the falsy expressions is considered truthy.

Other Coding Terms You Should Know

This section contains more coding terms that everyone should know. These are simple terms you will see within and outside of JavaScript as they are generally important in the programming field.


An algorithm is a method for solving a computational problem. In other words, it describes how to do something so that a computer system can do it repeatedly in the same way.


API is an abbreviation for Application Programming Interface. It is used by software to access data, server software, or other applications. APIs contain definitions and protocols used to build application software and integrate it into other programs. An API is compatible with web-based systems, operating systems, database systems, and computer hardware.


Bootstrap is a free and open-source front end development framework that allows you to create faster, easier, and more responsive websites, web apps, and mobile apps. It works with Chrome, Firefox, and Safari, as well as other modern web browsers.


A cache is a high-speed hardware or software component that stores data to allow for faster future data requests. It makes it easy for you to use previously used, retrieved, or computed data.

Data Structures

A data structure is a specialized format used to organize, process, retrieve, and store data. Data structures make it easy for users to access and work with the required data. They present information in a way that humans can understand.


A framework is a platform designed specifically for software development. You can use frameworks to create high-quality and low-level functional software that requires less attention, allowing you to focus on other aspects of your project.


HTML stands for HyperText Markup Language. It is a type of formatting system that is used to structure a web page and its content. HTML markup tags define document elements such as headings, paragraphs, and tables. They format a document so that it can be viewed by a web browser.


Libraries are collections of prewritten or precompiled code that can be utilized by other users to complete their tasks. Each programming language has a number of libraries that developers can use to create their programs.


PHP is an abbreviation for Hypertext Preprocessor. It is a widely used open-source general-purpose scripting language that can be encoded in HTML and is ideal for web development.

Version Control

Version control is also referred to as source control. It is the system in charge of tracking and managing changes to computer programs and software. They assist teams in managing changes to source code over time. An example of this is the platform Github.

Should You Learn JavaScript?

Yes, you should learn JavaScript for many reasons, including that it is the most popular coding language used for web development. Developers use it in both front end and backend development to make websites and applications more interactive and engaging for the user. It is also comparably fun to learn, has a low threshold of knowledge to get started, and is the only language native to web browsers.

JavaScript Terminology FAQ

What are the terms inevitably used in JavaScript?

Some of the terms that are inevitably used in JavaScript include VAR, loops, objects, prototypes, conditional, destructuring, Boolean, closures, and reserved words. These are all important fundamental terms to learn.

Is JavaScript hard to learn?

JavaScript is not hard to learn, even as a beginner to programming. It is one of the easiest programming languages to learn and has many libraries and resources that you can use to make the learning process even smoother.

What is the main use of JavaScript?

JavaScript is used mainly to create web pages and web applications and make them more interactive. It can also be used in both front end and backend development.

Is it worth learning JavaScript in 2023?

JavaScript is worth learning in 2023 as it is used to design many of the web pages available on the Internet today. It is also in high demand due to the uniqueness of interactive websites. Learning JavaScript in 2023 will be a great advantage to you.

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