DEV Community: Lajpat Gautam

React-quiz-app

Lajpat Gautam — Sun, 08 Feb 2026 04:04:00 +0000

React Quiz App

🧠 React Quiz App
An interactive, timer-based quiz application built using React, designed to evaluate users’ knowledge through dynamic questions and real-time score calculation.

This project highlights my hands-on understanding of React fundamentals, component-based architecture, and efficient state management.
🚀 Live Demo
🔗 Deployed on Netlify
👉 https://react-quiz-app-lajpat.netlify.app/

✨ Key Features
⏱️ 30-second timer for each quiz session

📊 Automatic score calculation

🔄 Dynamic question rendering

🧠 Smooth and user-friendly quiz flow

📱 Fully responsive UI (Mobile & Desktop)

⚡ Fast performance with optimized React components
🛠️ Tech Stack

React.js

JavaScript (ES6+)

HTML5

CSS3

Netlify (Deployment)

Screenshots

Home Screen

Result Screen

⚙️ Getting Started (Run Locally)

Follow these steps to run the project on your local machine:
1️⃣ Clone the repository
git clone https://github.com/Lajpatgautam/react-quiz-app.git

2️⃣ Navigate to the project directory
cd react-quiz-app

3️⃣ Install dependencies
npm install

4️⃣ Start the development server
npm start
The app will run at:
👉 http://localhost:3000

📌 What This Project Demonstrates

Strong understanding of React state & props

Component reusability and clean UI structure

Timer logic and conditional rendering

Real-world project deployment experience

Responsive design principles
📬 Contact

👤 Lajpat Gautam
🔗 GitHub: https://github.com/Lajpatgautam

🌐 Portfolio / Live Projects available on request

Deploying a react quiz app on EC2

Lajpat Gautam — Sun, 08 Feb 2026 03:47:16 +0000

This guide will help you deploy your React app on an AWS EC2 instance using Ubuntu.

1️⃣ Launch an EC2 Instance

Go to AWS Console → EC2 → Launch Instance.
Choose an Ubuntu AMI (Ensure it's Free Tier Eligible if using Free Tier).
Select an instance type (e.g., t2.micro for Free Tier).
Create a Key Pair for SSH access.
Configure Security Groups:
- Allow HTTP (Port 80) & HTTPS (Port 443) for public access.
- Allow SSH (Port 22) for remote login.

2️⃣ Connect to Your EC2 Instance

Once your instance is running, connect via SSH using your key pair:

ssh -i your-key.pem ubuntu@your-ec2-public-ip

3️⃣ Set Up the Environment

Update Ubuntu

Run the following command to update system packages:

sudo apt-get update && sudo apt-get upgrade -y

By default, Ubuntu does not have npm installed. Install it using:

sudo apt install npm -y

4️⃣ Deploy Your React App

Clone Your Repository

git clone <your-repository-link>

Navigate to Your Project Directory

cd your-project-name

Install Dependencies

npm install

Use --host Flag to Expose Vite Server on EC2

npm run dev -- --host(if you don't have dev then direct run "npm start")

Start the React App

npm run dev

5️⃣ Handling EC2 Public IP Changes

By default, AWS assigns a dynamic public IP that changes when the instance is restarted. To keep the same IP:

Attach an Elastic IP (AWS allows only 1 free Elastic IP in Free Tier).
Go to AWS Console → EC2 → Elastic IPs.
Allocate a new Elastic IP and associate it with your EC2 instance.

Now, your app will remain accessible even after a reboot.

✍️ Author: Lajpat Gautam

Cloud-Computing-learning

Lajpat Gautam — Sun, 08 Feb 2026 03:36:06 +0000

🌩️ What Is Cloud Computing?

Cloud computing refers to using computing resources such as servers, storage, databases, networking, and software through the internet instead of owning physical hardware.

Rather than buying and maintaining servers on your own premises, cloud users access resources hosted on remote data centers. These resources are available on demand, and users are charged only for what they actually consume.
In simple words, cloud computing allows applications and data to run on online servers instead of local machines.

⭐ Key Features of Cloud Computing

Scalability

Resources can be increased or reduced easily based on workload.

Elasticity

Systems automatically adjust capacity when demand changes.

High Availability

Services remain accessible with minimal downtime.

Agility

Resources can be provisioned quickly within minutes.

Fault Tolerance

Applications continue working even if a component fails.

Disaster Recovery

Data and applications can be restored after failures or disasters.

Pay-As-You-Go Pricing

Users pay only for the resources they use.

☁️ Cloud Service Models

🔹 Infrastructure as a Service (IaaS)

More control is given to the user

Cloud provider manages hardware and virtualization

User manages OS, applications, and data

Common use cases:

Virtual machines

Testing and development

Application migration

Examples:

AWS EC2

Azure Virtual Machines🔹 Infrastructure as a Service (IaaS)

More control is given to the user

Cloud provider manages hardware and virtualization

User manages OS, applications, and data

Common use cases:

Virtual machines

Testing and development

Application migration

Examples:

AWS EC2

Azure Virtual Machines

🔹 Platform as a Service (PaaS)

Responsibilities are shared

Provider manages OS, runtime, and infrastructure

User focuses only on application code

Ideal for:

Application development

Example:

Heroku

🔹 Software as a Service (SaaS)

Provider manages everything

Users access applications via browser

No installation required

Examples:

Gmail

Outlook

Microsoft 365

OneDrive

🔐 Shared Responsibility Model

The shared responsibility model explains who is responsible for what in cloud security.

Cloud Provider → Infrastructure, physical security, and underlying services

Customer → Data, user access, configurations, and applications

📌 Responsibility depends on whether you use IaaS, PaaS, or SaaS.

🌍 Cloud Deployment Models

Private Cloud

Dedicated environment

High security and control

Higher cost and maintenance

Public Cloud

Fully managed by provider

Cost-effective

No infrastructure management

Hybrid Cloud

Mix of private and public cloud

Sensitive data stays private

Multi-Cloud

Uses multiple cloud providers

Avoids vendor lock-in

🔌 API (Application Programming Interface)

An API is a set of rules that allows software systems to communicate with each other.

In cloud environments, APIs enable users to interact with:

Compute services

Storage

Databases

AI and ML services

📈 Scaling in Cloud Computing

Vertical Scaling

Increasing resource size

Example: Adding more RAM or CPU to a VM

Horizontal Scaling

Adding or removing instances

Common in high-traffic applications

🖥️ Virtualization

Virtualization allows multiple virtual machines to run on a single physical server.

Key benefits:

Better hardware utilization

Multiple OS on one machine

Cost efficiency

⚙️ Hypervisor

A hypervisor is software that:

Creates and manages virtual machines

Isolates multiple VMs on one host

Allows different OS to run simultaneously

📦 Containerization

Containerization is a lightweight alternative to virtualization, mainly used for microservices.

Key points:

Packages application with dependencies

Shares host OS kernel

Faster and lightweight

Solves “it works on my machine” issue

Best for:

Microservices

Scalable backend systems

⚠️ Containers cannot run a different OS kernel.

🏢 Datacenters, Regions & Availability Zones

Datacenter

A physical building that stores servers and networking equipment.

Region

A geographical area containing multiple datacenters.

Availability Zones

Isolated datacenters within a region

Ensure high availability and fault tolerance

🧩 Virtual Machines vs Containers

🖥️ Virtual Machines (VMs)

Each VM runs its own full operating system

Uses a hypervisor on top of physical hardware

More secure but heavier and slower

Requires more CPU, RAM, and storage

Best for:

Legacy applications

Strong isolation requirements

📦 Containers

Share the host operating system kernel

No separate OS for each application

Lightweight and fast

Starts in seconds

Best for:

Microservices architecture

High-scalability applications

DEV Community: Lajpat Gautam

React-quiz-app

React Quiz App

Screenshots

Home Screen

Result Screen

Deploying a react quiz app on EC2

1️⃣ Launch an EC2 Instance

2️⃣ Connect to Your EC2 Instance

3️⃣ Set Up the Environment

Update Ubuntu

4️⃣ Deploy Your React App

5️⃣ Handling EC2 Public IP Changes

Now, your app will remain accessible even after a reboot.

Cloud-Computing-learning

🌩️ What Is Cloud Computing?

⭐ Key Features of Cloud Computing

Scalability

Elasticity

High Availability

Agility

Fault Tolerance

Disaster Recovery

Pay-As-You-Go Pricing

☁️ Cloud Service Models

🔹 Infrastructure as a Service (IaaS)

Examples:

Azure Virtual Machines🔹 Infrastructure as a Service (IaaS)

Common use cases:

Examples:

🔹 Platform as a Service (PaaS)

Ideal for:

Example:

🔹 Software as a Service (SaaS)

Examples:

🔐 Shared Responsibility Model

📌 Responsibility depends on whether you use IaaS, PaaS, or SaaS.

🌍 Cloud Deployment Models

Private Cloud

Public Cloud

Hybrid Cloud

Multi-Cloud

🔌 API (Application Programming Interface)

📈 Scaling in Cloud Computing

Vertical Scaling

Example: Adding more RAM or CPU to a VM

Horizontal Scaling

🖥️ Virtualization

⚙️ Hypervisor

📦 Containerization

🏢 Datacenters, Regions & Availability Zones

Datacenter

Region

Availability Zones

🧩 Virtual Machines vs Containers

🖥️ Virtual Machines (VMs)

📦 Containers

✍️ Author: Lajpat Gautam