Principles of responsive design Responsive design is a fundamental approach in modern web development that ensures websites and applications adapt seamlessly to different screen sizes, resolutions, and devices—from smartphones to large desktop monitors. It focuses on delivering an optimal user experience regardless of how users access the content. 1. Fluid Layouts Instead of fixed-width layouts, … Read more
CSS Transitions: transition-property, transition-duration, transition-timing-function CSS Transitions enable you to smoothly animate changes to CSS property values over a specified duration, enhancing the visual interactivity and responsiveness of web interfaces. What Are CSS Transitions? CSS Transitions allow HTML elements to change property values gradually, rather than instantly, when triggered by events like :hover, :focus, or … Read more
CSS Variables (Custom properties): reusable values across stylesheets CSS Variables, also known as custom properties, allow developers to store reusable values in a stylesheet, making CSS easier to maintain, update, and scale across projects. What Are CSS Variables? CSS variables are defined using the — prefix and can hold values like colors, font sizes, spacing, … Read more
Introduction to CSS frameworks: Bootstrap, Tailwind CSS, Bulma CSS frameworks provide predefined styles, utilities, and components that speed up the development process, promote consistency, and help create responsive and modern UI designs with less custom CSS. Let’s explore three popular CSS frameworks: Bootstrap, Tailwind CSS, and Bulma. 1. Bootstrap Bootstrap is a widely-used front-end framework … Read more
Writing clean, modular, and maintainable CSS Clean, modular, and maintainable CSS is essential for building scalable and easy-to-manage web applications. Whether you’re working solo or with a team, well-structured CSS prevents code duplication, improves readability, and simplifies long-term maintenance. 1. Use Meaningful Naming Conventions Avoid vague class names like .blue, .box1, or .main-div. Use semantic … Read more
What is System Design? System design is the process of defining the architecture, components, modules, interfaces, and data flow for a complex software system to meet specific functional and non-functional requirements. It involves planning how different parts of a system interact, scale, maintain reliability, and perform efficiently under load. Key Aspects of System Design Scalability … Read more
Latency vs. Throughput In system design and performance engineering, latency and throughput are two key metrics used to measure how well a system performs under different conditions. Though often mentioned together, they represent very different aspects of performance. What is Latency? Latency is the time delay between a request and its corresponding response. It measures … Read more
HTTP/HTTPS What is HTTP? HTTP is the foundational protocol for communication on the World Wide Web, enabling data exchange between browsers (clients) and web servers. How HTTP Works: When a browser sends a request to a server, the server processes it and returns a response—typically HTML, CSS, or JavaScript files. HTTP is stateless, meaning each … Read more
SQL vs. NoSQL Overview: SQL (Structured Query Language) and NoSQL (Not Only SQL) databases are two broad categories of database technologies, each with different structures, use cases, and benefits. SQL Databases Definition: SQL databases are relational databases that use structured schemas with rows and columns. Data is stored in tables, and relationships between data are … Read more
Horizontal vs. vertical scaling Scaling is a core concept in system design used to handle increased load, users, or data by enhancing system capacity. The two primary strategies are horizontal scaling and vertical scaling. Horizontal Scaling (Scaling Out) Definition: Horizontal scaling means adding more machines or nodes to your system to distribute the load. How … Read more
Client-side vs. server-side caching Caching is a technique used to store copies of files or data in locations that are closer to the user, which can help reduce load times and improve performance. Both client-side and server-side caching have distinct uses and advantages. Client-Side Caching Client-side caching refers to storing data in the user’s browser … Read more
Event-driven architecture Overview Event-Driven Architecture (EDA) is a software design pattern in which components communicate by emitting and responding to events, enabling asynchronous interactions and loose coupling between services. Core Concepts Event: A signal that something has happened within a system, such as “user_signed_up” or “item_added_to_cart”. Producer: The service or component that generates and emits … Read more
Designing URL shorteners, file storage, newsfeeds, etc. Designing a URL Shortener Use Case: A URL shortener service converts long URLs into short aliases to make sharing easier and track usage. Core Features: Short link generation Redirection to original URLs Analytics tracking (clicks, sources) Design Considerations: Use of base62 or hash functions to generate short IDs … Read more
Authentication and Authorization Authentication The process of verifying the identity of a user or system. Username and password authentication Multi-factor authentication (MFA) Biometric authentication (fingerprint, facial recognition) OAuth and SSO (Single Sign-On) systems Authorization The process of granting or denying access to resources based on verified identities. Role-based access control (RBAC) Attribute-based access control (ABAC) … Read more
Communication and requirement gathering Definition: Communication and requirement gathering are foundational phases in any software or system design process, where stakeholders, developers, and designers collaborate to identify what the system should achieve. Why It Matters: Ensures alignment between stakeholders and development teams. Helps avoid misunderstandings and scope creep. Sets a clear direction for the design … Read more
What is React and why use it What is React? Definition: React is a free and open-source JavaScript library developed by Facebook for building user interfaces, especially single-page applications (SPAs), where data changes frequently over time. Core Concept: React allows developers to create large web applications that can update and render efficiently in response to … Read more
Functional components and props Functional components are the most common and modern way to build UI in React. They are simple JavaScript functions that return JSX and describe what the UI should look like. Props, short for “properties,” allow data to be passed from a parent component to a child component, making components dynamic and … Read more
Introduction to React Hooks React Hooks are functions that let you use state and other React features in functional components. They were introduced to simplify component logic and eliminate the need for class-based components in most cases. Why Hooks Were Introduced Before Hooks, state and lifecycle features were only available in class components. Hooks allow … Read more
Controlled vs uncontrolled components Controlled and uncontrolled components are two approaches to handling form inputs and user data in React. Understanding their differences is key to managing form state effectively and building predictable user interfaces. What Are Controlled Components Controlled components have their form data managed by React state. The component’s input values are set … Read more
Installing and configuring React Router React Router is a popular library for managing navigation and routing in React applications. It enables developers to create single-page applications (SPAs) with multiple views and URL-based navigation. Installing React Router To start using React Router, you need to install it via npm or yarn. The core package for web … Read more
Lifting State up Lifting state up in React refers to the practice of moving shared state to the closest common ancestor of components that need to access or modify that state. It allows sibling components to communicate and remain synchronized through a shared parent. Why Lift State Up State is often local to a component, … Read more
Fetching data using fetch and Axios Data fetching is a core part of building dynamic web applications. In React, two common approaches for making HTTP requests are the native fetch API and the third-party library Axios. Both allow you to retrieve data from external sources like APIs and integrate it into your application. Using the … Read more
Code splitting with React.lazy and Suspense Code splitting is a performance optimization technique that breaks your React application into smaller bundles, loading only the code needed for the current view. This improves initial load times and overall app responsiveness. What Is React.lazy React.lazy is a built-in React function that enables dynamic import of components. It … Read more
Building React apps for production Building React apps for production involves optimizing performance, reducing bundle size, and preparing your app for deployment using tools and configurations that ensure fast, efficient, and secure delivery to users. Key Steps in Production Builds Use npm run build or yarn build to generate an optimized build Minify and compress … Read more
Unit testing with Jest Unit testing with Jest in React involves testing individual components or functions in isolation to ensure they work as expected. Jest is a popular JavaScript testing framework developed by Meta, and it’s commonly used with React for its simplicity, speed, and powerful features. What Is Jest Jest is a zero-configuration testing … Read more
Defining and Creating Classes In Object-Oriented Programming, classes serve as templates for creating objects. They define the structure and behavior that objects will have through properties and methods. Defining a Class A class is defined using a specific syntax in programming languages like Python, Java, or C++ It typically includes a constructor method to initialize … Read more
What is Object-Oriented Programming? What is Object-Oriented Programming? Object-Oriented Programming (OOP) is a programming paradigm based on the concept of “objects,” which contain data and behavior. It helps structure code into reusable and organized components that mirror real-world entities. Core Concepts of OOP Class: A blueprint for creating objects that defines properties and methods Object: … Read more
Access modifiers (public, private, protected) Access modifiers in Object-Oriented Programming control the visibility and accessibility of class members (fields and methods), helping to enforce encapsulation and protect data integrity. Public Members declared as public are accessible from anywhere in the program They can be accessed by other classes, subclasses, and even outside the package or … Read more
Concept of inheritance Inheritance is a core concept in Object-Oriented Programming that allows one class (called the child or subclass) to acquire the properties and behaviors (fields and methods) of another class (called the parent or superclass). It promotes code reuse, hierarchy, and a clear organizational structure in complex software systems. Key Idea of Inheritance … Read more
Static (compile-time) vs dynamic (run-time) polymorphism Polymorphism is an essential concept in object-oriented programming that allows objects to be treated as instances of their parent class rather than their actual class. It enables a single interface to represent different types of behaviors. Polymorphism is categorized into static and dynamic based on when the method to … Read more