DEV Community: Claire Charles

Data Types: The JavaScript Structure

Claire Charles — Thu, 17 Jul 2025 18:20:09 +0000

JavaScript, at its core, works with variables and data types just as binary code does with just 1s and 0s. These are quite essential for understanding and manipulating information within our code. In this article, we will be focusing on the various data types in JavaScript.

What are Data Types

It's as simple as it sounds-- Data types are the "Types of data".

As defined in Computer Science, it is a classification that defines the types of values variables can hold and how the computer should interpret them. In JavaScript, these data types could be classified into 2 main groups:

Primitive
Non-Primitive

LET'S GET INTO IT!

Primitive data types

These are simple and immutable, meaning their value cannot be changed after creation. There are 7 primitive data types in JavaScript:

String
Number
Boolean
Undefined
Null
Symbol
BigInt

String

The string type is used to represent a sequence of characters, which could be names or special messages. They are declared using single or double quotes or backticks. Strings have some properties, such as indexability and immutability, meaning that each character in a string can be accessed by its numerical index (starting from 0).

let name = "Claire";
let age = "5";

console.log(name); // Claire
console.log("My name is " + name + "." + " I am " + age); // My name is Claire. I am 5

You can On the last line of code, we have a + character used after the string; this can be used to join another value to your string -- It's called Concatenation.

Number

The number type is used to represent both integer(whole number) and floating-point numbers (decimal). They can be used to perform various mathematical operations.
There is a range of numbers in JavaScript that is defined by Numbers.MAX_VALUE and Numbers.MIN_VALUE, which represents the largest and smallest numbers. Outside the range of what's possible, JavaScript offers some Special number values like:

Infinity: A positive number greater than the maximum value in JavaScript
-Infinity: A negative number less than the minimum value in JavaScript
NAN: This means Not a Number. Represents a computational error for when an operation cannot be expressed as a number.

let subject1 = 12;
console.log(subject1) // 12

let subject2 = 1.3;
console.log(subject2) // 1.3

let result = 12 / 0;
console.log(result) // Infinity

let subject3 = 'Claire' / 2;
console.log(subject3) // NAN

Boolean

The boolean type represents two possible values: True or False.

let isStudent = true;
console.log(isStudent) // true

let isStudentRich = false;
console.log(isStudentRich) // false

Guiding rules for Boolean:

Strings: An empty string ("") will be converted to false, and any other string will be converted to true.
Numbers: Zero (0) and NaN (Not a Number) will be converted to false, and any other number will be converted to true.
Objects: All objects, including arrays and functions, will be converted to true.
Undefined: Undefined will be converted to false.

Undefined

The undefined type represents a variable that has been declared but not assigned a value. It is used to indicate the absence of a value

let webBridge;
console.log(webBridge) //undefined

Null

The Null type is used to represent an empty or unknown value. This is used intentionally

let money = null;
console.log(money) //null

Symbol

This is a unique value used as an identifier for object properties. They help create unique values in objects, preventing conflicts with other properties.

let name = Symbol("Claire");
let name2 = Symbol("Claire");
console.log(name == name2); //false

You can see this code has the same values passed to it, but they do not equal each other.

BitInt

BigInt is a type that represents a whole number greater than the JavaScript maximum integer

let b = BigInt("0b1010101001010101001111111111111111");
console.log(b); // 11430854655n

Non-Primitive Types

There are complex data structures that hold multiple values and more complex data. Unlike primitive types that directly store actual values, non-primitive types store references to the values.

Object:

An object is a data structure used to store data in key-value pairs. They are the fundamental blocks of JavaScript, as nearly everything used in the language is an object-- even functions.

let web3Bridge = {
    type: "Web3 Advance",
    name: "Claire"
}
console.log(web3Bridge.type) // Web3 Advance

Arrays

An array is a special type of object used for storing an ordered collection of values, usually indexed by numbers.

let members = ["Claire", "Joy", "Emmanuel"];
console.log(members); //  ["Claire", "Joy", "Emmanuel"]

Functions

A function is a reusable block of code designed to perform a particular task.

function addNumbers (num1, num2) {
    return num1 + num2;
}

console.log(addNumbers(4, 4)); // 8
console.log(addNumbers(3, 8)); // 11

Impact of tech on kids/teens

Claire Charles — Sun, 23 Oct 2022 18:37:10 +0000

A lot of kids these days have broken their way into the tech ecosystem and it has made a huge impact in their lives. In this article, I will be sharing inspiring stories of kids who have bridged their way into the tech ecosystem.

The Impact of tech on kids

Tech has played a huge impact on the life of so many kids/teens. These impacts include:

Creativity and freedom of expression
Socialization and relationship building
Independence and empowerment
Problem solving and perseverance
Entrepreneurial spirit
Learning enhancement
In-demand job prep

Here is the story of a list of kids who are succeeding in the tech ecosystem.

Gitanjali Rao

Gitanjali Rao is a 16 years old author, speaker, community volunteer, science enthusiast, STEM promoter, and board member. She is a youth advocate for UNICEF. When Rao was younger, she heard of the water flint crisis and became interested in ways to measure the lead content in water. This led to her developing a device called Tethys based on carbon nanotubes that could send water quality information via Bluetooth. Rao developed an app 'Kindly' that uses Artificial Intelligence which prevents cyberbullying. She has won a lot of awards and challenges like Discovery Education 3M Young Scientist Challenge, United States Environmental Protection Agency President's Environmental Youth Award, Laureate of the Young Activists Summit at UN Geneva. IShe is hence, the first person to receive TIME magazine's Kid of the Year designation.

Opemipo Disu

Opemipo Disu is a 17 years old web developer, 2020 IBM Champion, JamStack developer, Agility CMS advocate. Opemipo is passionate about helping people with his available resources, by making the web more accessible via Youtube, Linkedln, and Instagram, He started his tech career at the age of 11, his Dad got him all the tools he needed for work back then. He loves making differences. He is currently working on a project to help stop cyberbullying. In 2019, Opemipo was nominated to be an IBM champion for Developers in 2020 and was later selected in January 2020. He works with languages under web development, software development, and AI technologies. He had his very first Laptop at the age of 5 and started contributing to tech communities at the age of 11. Since his bridge into the tech ecosystem, he has achieved a lot, He has inspired 10 thousand kids on 5 different continents around the world, he is widely recognized by the IBM community, He has won 5 awards since his break into tech as a developer advocate Apart from that, He has spoken at over 50 dev conferences.

Bereket Semagn

Bereket Semagn is a 14 years old developer, designer, and entrepreneur who has a passion for AI and how it can change the future moving forward. He loves creating products that help teams and individuals become productive and engaged. He started his tech journey in 2020 and since then he has been publicly noticed. He created a Lunar theme for VsCode which had +3k installations. he has built over 10 products in 2021.

Lella Violet Halloum

Lella is a 18 years old, British Lebanese, and is passionate about ‘tech for good’ & closing the digital divide. She is a frequent speaker, thought leader, and advocate for young people. She brings her personal mission to life by engaging thousands of students globally through tech events and social media and, with IBM's support, she creates student-led webinars that are entirely for, with, and by youth. Through her work, Lella strides to diversify the industry by creating more opportunities for young people, particularly underserved & underrepresented communities and those with non-traditional academic backgrounds, highlighting the important role young people play in tech and wider society. Lella has achieved a lot in the tech industry, from winning the 2021 Diana Award to winning Women of the Future Awards 2021: Young Star, to becoming the IBM champion.

Samaria Mehta

Samaira Mehta is an American coder and inventor. She is the founder and chief executive officer of CoderBunnyz. She began coding when she was 6 years old with her father as her teacher. She created the board game CoderBunnyz, with the help of her little brother, to teach other children how to code. Samaria speaks at workshops and conferences including at Microsoft, Intel, and Google. She spoke at the 2019 C2 Montréal Conference. Samaria aims to eliminate gender bias and increase the number of women in engineering. she has achieved a lot like the $2,500 second-place prize at Think Tank Learning's Pitchfest. She received a letter from former first lady Michelle Obama.

Tanmay Bakshi

Tanmay Bakshi is a 18 years old Canadian author, Machine Learning Developer, TED & Keynote Speaker, and media personality. Tanmay has been coding since he was 5 years old. To date, he has addressed over 200,000 people at international conferences, speaking about Computational Thinking, The 4th Industrial Revolution, Machine Learning, and Innovation. His goal to reach out to 100,000 aspiring coders to help them learn how to code has him holding countless workshops and seminars in schools and universities across the globe. Since his bridge into the tech ecosystem, he has won awards like the Twilio Doer Award, Knowledge Ambassador Award, Life Mentor Award, he’s a Global Goodwill Ambassador at LinkedIn, and an IBM Champion for Cloud.

Diana Ashktorab

Diana is an 9-year-old CodeNewbie who loves AI. Her goal is to create a robot someday to do children's homework so they can use their time for more creative stuff. She started her coding journey in August 2020, with Scratch and since then she has made a lot of amazing games.

Claire Charles

Yes, this is me, I am a 14 years old web3 developer, technical writer, and open-source contributor. I am passionate about contributing to open-source, public speaking, and coding. I began my coding journey in April 2020, and tho I haven't achieved much but I have a goal to bring more people into the tech ecosystem and to show them that they can achieve a lot at a young age.