🚀 Web Development Interview Questions with Answers — Part 8: APIs & Backend Concepts

🧠 166. What is an API?

API stands for: 👉 Application Programming Interface

An API allows different software applications to communicate with each other.

Example:

When a weather app fetches weather data from a server, it uses an API.

Benefits:

✅ Data sharing

✅ System integration

✅ Automation

🧠 167. Difference Between REST and GraphQL

Concept | REST | GraphQL

Endpoints | Multiple endpoints | Single endpoint

Response structure | Fixed response structure | Client chooses data

Data fetching | Over-fetching possible | Fetch only needed data

Complexity | Simpler | More flexible 

Example:

REST: GET /users/1

GraphQL:

{
  user(id:1){
    name
    email
  }
}

🧠 168. What is a RESTful API?

RESTful API follows REST architectural principles.

Key Principles:

Stateless

Client-Server Architecture

Uniform Interface

Resource-Based URLs 

Example:

GET /users

POST /users

PUT /users/1

DELETE /users/1

🧠 169. What are HTTP Status Codes?

HTTP status codes indicate server response status.

Categories:

Range | Meaning

1xx | Informational

2xx | Success

3xx | Redirection

4xx | Client Error

5xx | Server Error 

🧠 170. Explain 200, 201, 400, 401, 403, 404, and 500

Code | Meaning

200 | OK

201 | Created

400 | Bad Request

401 | Unauthorized

403 | Forbidden

404 | Not Found

500 | Internal Server Error 

Example:

res.status(404).json({
   message: "User Not Found"
});

🧠 171. What is API Testing?

API Testing verifies functionality, performance, and security of APIs.

Checks:

✅ Response data

✅ Status codes

✅ Authentication

✅ Performance 

Tools:

Postman

Insomnia

Swagger 

🧠 172. What is Postman?

Postman is a tool used to test APIs.

Features:

✅ Send API requests

✅ Test endpoints

✅ Automate testing

✅ Manage collections 

Example:

GET https://api.example.com/users

🧠 173. What is WebSocket?

WebSocket enables real-time two-way communication between client and server.

Uses:

Chat applications

Online gaming

Live notifications

Stock market updates 

Benefits:

✅ Real-time communication

✅ Low latency 

🧠 174. Difference Between Polling and WebSocket

Concept | Polling | WebSocket

Connection | Client repeatedly asks server | Persistent connection

Network usage | Higher network usage | Efficient communication

Updates | Slower updates | Real-time updates 

🧠 175. What is Microservice Architecture?

Microservices divide an application into small independent services.

Example:

User Service

Payment Service

Order Service

Notification Service 

Benefits:

✅ Scalability

✅ Independent deployment

✅ Easier maintenance 

🧠 176. What is Monolithic Architecture?

Monolithic architecture combines all components into one application.

Example:

Frontend

Backend

Database

↓

Single Application 

Advantages:

✅ Simpler development initially 

Disadvantages:

❌ Harder to scale 

🧠 177. What is Caching?

Caching stores frequently accessed data temporarily for faster retrieval.

Benefits:

✅ Faster performance

✅ Reduced database load

✅ Improved user experience 

Example:

cache.set("users", data);

🧠 178. What is Redis?

Redis is an in-memory database commonly used for caching.

Features:

✅ Extremely fast

✅ Key-value storage

✅ Session management 

Example:

redis.set("user", userData);

consistency feels boring until it starts changing your life.

This is why continuous learning is crucial if you're truly interested in professional growth.

And taking all the steps requires strong stamina and readiness to suffer along the way.

✅ 8-Week Beginner Roadmap to Learn Web Development 🌐✨

🗓️ Week 1: Build a Strong Foundation
⦁ Learn HTML: structure web content with tags, lists, tables, forms
⦁ Learn CSS: style webpages using selectors, properties, layouts
⦁ Practice on interactive platforms like freeCodeCamp or The Odin Project

🗓️ Week 2: Dive into JavaScript Basics
⦁ Understand variables, functions, loops, conditionals, events
⦁ Get familiar with making pages interactive (e.g., to-do list, calculator)
⦁ Use small projects to solidify learning

🗓️ Week 3: Advanced CSS & Responsive Design
⦁ Learn Flexbox, Grid, media queries for responsive layouts
⦁ Explore CSS frameworks like Bootstrap or Tailwind CSS
⦁ Practice building mobile-friendly web pages

🗓️ Week 4: Front-End Frameworks Basics
⦁ Choose one: React.js (most popular), Vue.js (easy for beginners), or Angular
⦁ Learn component-based architecture and state management basics
⦁ Build small UI components (buttons, forms, modals)

🗓️ Week 5: Version Control with Git & GitHub
⦁ Learn Git basics: init, add, commit, branch, merge, push
⦁ Host projects on GitHub and understand collaboration workflows
⦁ Practice by pushing your previous week projects

🗓️ Week 6: Back-End Basics
⦁ Understand what servers and APIs are
⦁ Learn a backend language like Node.js (JavaScript) or Python (recommended for beginners)
⦁ Explore databases basics (SQL or NoSQL) and CRUD operations

🗓️ Week 7: Building Full-Stack Applications
⦁ Combine front-end and back-end skills in simple projects
⦁ Learn about RESTful APIs, authentication & authorization basics
⦁ Deploy projects on platforms like Heroku, Netlify, or Vercel

🗓️ Week 8: Capstone Project + Deployment
⦁ Build a complete web app (e.g., blog, to-do list, portfolio) from scratch
⦁ Make sure it’s responsive, interactive, and connected to a database
⦁ Deploy and share it online (GitHub + hosting platform)

💡 Tips:
⦁  Code daily and build small projects to practice concepts
⦁  Use resources like freeCodeCamp, The Odin Project, or YouTube tutorial

🪼WAVE TIME ⏰️

⭐️ 1K+ Subscriber ያላችሁ እና

Channel ማሳደግ የምትፈልጉ
→ DM @waverpulse & “WAVE” ብላችሁ Channel Link ላኩ።

🚫 Educational ቻናሎች ብቻ |
❌ 1K በታች/sexual content |

🆓 No Payment
Dm @waverpulse

5🌐 Complete Web Development Roadmap

1. 🧠 Web Development Fundamentals

• What is web development

• How the Internet works

• How websites work

• Client and server

• Browser, Web server

• HTTP & HTTPS, URL

• Domain names, DNS

• Frontend vs Backend

• Static vs Dynamic websites

• Developer tools, Code editors

• Files and folders, Command line basics

• Project: Create and publish your first basic webpage

2. 🏗️ HTML — Structure of Websites

Learn how to build the structure of a webpage.

• HTML syntax, Elements and tags

• HTML document structure

• Headings, Paragraphs, Links, Images

• Lists, Tables

• Forms, Input fields, Buttons

• Attributes, Semantic HTML

• Accessibility, HTML best practices

• Project: Build a multi-page personal website

3. 🎨 CSS — Designing Websites

Learn how to make websites attractive and responsive.

• CSS syntax, Selectors

• Colors, Units, Fonts, Typography

• Backgrounds, Borders

• Box model, Margin, Padding, Width & height

• Display, Positioning

• Flexbox, CSS Grid

• Pseudo-classes, Pseudo-elements

• Variables, Transitions, Animations

• Responsive design, Media queries

• Projects: Landing page, responsive website, portfolio website

4. 💻 JavaScript — Programming Fundamentals

• JavaScript basics, Variables, Data types

• Operators, Strings, Numbers

• Conditions, Loops, Functions, Scope

• Arrays, Objects

• Array methods, Object methods

• Destructuring, Spread/rest

• Error handling

• Projects: Calculator, number guessing game, to-do app, quiz app

5. 🌐 JavaScript in the Browser

Learn how JavaScript controls webpages.

• DOM, Selecting elements, Modifying elements

• Events, Event listeners, Event propagation

• Forms, Form validation

• Local storage, JSON

• Fetch API, Promises, Async/await

• Working with APIs

• Projects: Weather application, expense tracker, API-based app

6. 🔧 Git & GitHub

Learn the tools developers use to manage their code.

• Git, Repository, Commit, Branch, Merge

• Push, Pull, GitHub, Pull requests

• README files, Branching workflow

• Merge conflicts, Collaboration

• Project: Build a professional GitHub portfolio

7. 🚀 Advanced JavaScript

Go deeper into JavaScript before learning a framework.

• Execution context, Call stack, Scope, Closures

• this, Prototypes, Prototype chain, Classes, Modules

• Event loop, Microtasks & macrotasks

• Asynchronous programming

• Debouncing, Throttling

• Memory management, Performance optimization

• Project: Build an advanced JavaScript application

8. ⚛️ React

Now learn modern frontend development.

•

Fundamentals:

• Why React, Components, JSX

• Props, State, Events

• Conditional rendering, Lists, Forms, Composition

•

Hooks:

• useState, useEffect, useRef, Context, Custom hooks

•

Advanced:

• Routing, API integration, Authentication, Protected routes

• State management, Performance, Lazy loading, Code splitting, Error handling, Testing

•

Projects: E-commerce frontend, admin dashboard, social media app

9. 🔷 TypeScript

• Why TypeScript, Types, Type inference

• Interfaces, Type aliases, Functions, Objects, Arrays

• Union types, Intersection types, Generics

• Type narrowing, Utility types

• TypeScript with React

• Project: React + TypeScript application

🔊🗞️ Breaking news 🗞️

😨ኢራን ወደ ኢትዮጵያ ሚሳኤል ልታስወነጭፍ ነው😨

እንዲህ የሚል ዜና ቢወጣ እንኳን ለመደበቅ መረጃ የምታገኙበት አሪፍ የዜና ቻናል የላችሁም❗️
ኑ ተቀላቀሉን😁

🪼ARE NATURAL OR SOCIAL 👩‍🎓👨‍🎓