Web Development - HTML, CSS & JavaScript
Learn to code and become a Web Developer with HTML, CSS, JavaScript , Reactjs, Wordpress, PHP, Mern & Nodejs knowledge Managed by: @love_data
Show more📈 Analytical overview of Telegram channel Web Development - HTML, CSS & JavaScript
Channel Web Development - HTML, CSS & JavaScript (@javascript_courses) in the English language segment is an active participant. Currently, the community unites 55 643 subscribers, ranking 2 313 in the Technologies & Applications category and 6 248 in the India region.
📊 Audience metrics and dynamics
Since its creation on невідомо, the project has demonstrated rapid growth, gathering an audience of 55 643 subscribers.
According to the latest data from 26 August, 2026, the channel demonstrates stable activity. Although there has been a change in the number of participants by 322 over the last 30 days and by 10 over the last 24 hours, overall reach remains high.
- Verification status: Not verified
- Engagement rate (ER): The average audience engagement rate is 3.26%. Within the first 24 hours after publication, content typically collects 1.23% reactions from the total number of subscribers.
- Post reach: On average, each post receives 1 815 views. Within the first day, a publication typically gains 687 views.
- Reactions and interaction: The audience actively supports content: the average number of reactions per post is 3.
- Thematic interests: Content is focused on key topics such as javascript, css, object, html, array.
📝 Description and content policy
The author describes the resource as a platform for expressing subjective opinions:
“Learn to code and become a Web Developer with HTML, CSS, JavaScript , Reactjs, Wordpress, PHP, Mern & Nodejs knowledge
Managed by: @love_data”
Thanks to the high frequency of updates (latest data received on 27 August, 2026), the channel maintains relevance and a high level of publication reach. Analytics show that the audience actively interacts with content, making it an important point of influence in the Technologies & Applications category.
console.log(Object.keys(person));
Output: ["name","age"]
🚀 17. Object.values()
Returns all values.
console.log(Object.values(person));
Output: ["Deepak",25]
🔥 18. Object.entries()
Returns key-value pairs. console.log(Object.entries(person));
Output: [["name","Deepak"], ["age",25]]
📦 19. Destructuring Objects
Extract values easily.
const person = { name:"Deepak", age:25 };
const { name, age } = person;
⚡ 20. Spread Operator
Copy objects.
const person = { name:"Deepak" };
const updated = {...person, city:"Pune" };
🎯 Real Interview Example
Array of Objects
const employees = [
{ id:1, name:"John" },
{ id:2, name:"Mike" }
];
console.log(employees[0].name);
Output: John
⭐ Most Important Topics For Interviews
🔥 Arrays
🔥 Objects
🔥 map()
🔥 filter()
🔥 reduce()
🔥 Destructuring
🔥 Spread Operator
🔥 Object.keys()
🔥 Object.values()
🔥 Array of Objects
📝 Mini Practice Questions
Easy:
✅ Find largest number in array,
✅ Sum all array elements,
✅ Count array length
Medium:
✅ Remove duplicates,
✅ Find second largest number,
✅ Reverse array
Advanced:
✅ Group objects by property,
✅ Custom map() method,
✅ Flatten nested arrays
Double Tap ❤️ For More
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1.59 ₽ · /balance_helpconst fruits = ["Apple", "Mango", "Banana"];
Access Elements:
console.log(fruits[0]);
Output: Apple
Important: Array indexing starts from 0.
⚡ 2. Creating Arrays
Method 1: const numbers = [10, 20, 30];
Method 2: const numbers = new Array(10, 20, 30);
🔥 3. Array Methods
push() Adds element at the end.
const arr = [1, 2];
arr.push(3);
console.log(arr);
Output: [1, 2, 3]
pop() Removes last element. arr.pop();
unshift() Adds element at beginning. arr.unshift(0);
shift() Removes first element. arr.shift();
🔄 4. Loop Through Arrays
for Loop
const nums = [1,2,3];
for(let i=0; i<nums.length; i++){
console.log(nums[i]);
}
for...of
for(let num of nums){
console.log(num);
}
🎯 5. map()
Creates a new array by transforming elements.
Example:
const nums = [1,2,3];
const doubled = nums.map(num => num * 2);
console.log(doubled);
Output: [2, 4, 6]
🔥 6. filter()
Returns elements matching condition.
Example:
const nums = [1,2,3,4,5];
const even = nums.filter(num => num % 2 === 0);
console.log(even);
Output: [2, 4]
🚀 7. reduce()
Reduces array to single value.
Example:
const nums = [1,2,3,4];
const sum = nums.reduce((total,num) => total + num, 0);
console.log(sum);
Output: 10
🧩 8. find()
Returns first matching element.
const users = [10,20,30,40];
const result = users.find(num => num > 20);
console.log(result);
Output: 30
📋 9. includes()
Checks if value exists.
const fruits = ["Apple","Mango"];
console.log(fruits.includes("Apple"));
Output: true
🔥 10. Remove Duplicates
const nums = [1,2,2,3,3];
const unique = [...new Set(nums)];
console.log(unique);
Output: [1, 2, 3]
📦 PART 2: JavaScript Objects
🧠 11. What is an Object?
An object stores data in key-value pairs.
Example:
const person = {
name: "Deepak",
age: 25,
city: "Bengalore"
};
⚡ 12. Access Object Properties
Dot Notation: console.log(person.name);
Bracket Notation: console.log(person["name"]);
🔥 13. Add New Property
person.country = "India";
console.log(person);
❌ 14. Delete Property
delete person.city;
🔄 15. Loop Through Objects
for...in
for(let key in person){
console.log(key, person[key]);
}function reverseString(str) {
return str.split('').reverse().join('');
}
4️⃣ Find the max number in an array
const max = Math.max(...arr);
5️⃣ Write a function to check if a number is prime
function isPrime(n) {
if (n < 2) return false;
for (let i = 2; i <= Math.sqrt(n); i++) {
if (n % i === 0) return false;
}
return true;
}
6️⃣ What is closure in JavaScript?
Answer:
A function that remembers variables from its outer scope even after the outer function has returned.
7️⃣ What is event delegation?
Answer:
Attaching a single event listener to a parent element to manage events on its children using event.target.
8️⃣ Difference between == and ===
Answer:
- == checks value (with type coercion)
- === checks value + type (strict comparison)
9️⃣ What is the Virtual DOM?
Answer:
A lightweight copy of the real DOM used in React. React updates the virtual DOM first and then applies only the changes to the real DOM for efficiency.
🔟 Write code to remove duplicates from an array
const uniqueArr = [...new Set(arr)];
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