FE Interview Hub

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QUESTION BANK

Question Bank

185

Explain the CSS Box Model and the difference between box-sizing values

What is the Event Loop? Explain the relationship between Call Stack and Task Queue

JavaScript Advanced

What is the Prototype Chain? How does JavaScript inheritance work?

JavaScript Intermediate

What are the advantages of Vue 3 Composition API over Options API?

Vue 3 Intermediate

What is LCP? How do you optimise it to meet Core Web Vitals standards?

Web Vitals Advanced

What is a Closure?

JavaScript Basic

What is HTML Semantic Markup?

Where should <script> and <link> be placed in HTML?

How to include CSS in HTML? What is the priority order?

HTML Intermediate

What is the difference between async and defer in <script>?

HTML Intermediate

Explain CSS Selector Specificity

What is 0.1 + 0.2 in JavaScript? Why? How to avoid floating-point issues?

JavaScript Intermediate

What is the difference between px, em, and rem in CSS?

How to center an element horizontally and vertically in CSS?

CSS Intermediate

What is the difference between display: inline and display: block?

What is the difference between display: none and visibility: hidden?

Explain the CSS position property and its values

CSS Intermediate

When should you use JPG, PNG, WebP, or SVG in frontend development?

What are CSS pseudo-classes and pseudo-elements?

CSS Intermediate

What are Reflow and Repaint? How do you optimise them?

Web Vitals Intermediate

What is throttle? How do you implement a throttle function?

Web Vitals Intermediate

What are the ways to optimise front-end performance?

Web Vitals Advanced

GraphQL vs REST API: Core Differences and When to Choose GraphQL

categories.api-design Intermediate

API Versioning Strategies: Trade-offs and Best Practices

categories.api-design Intermediate

What is debounce? How do you implement a debounce function?

Web Vitals Intermediate

Explain when DOMContentLoaded, load, beforeunload, and unload are fired

Browser Internals Basic

What are the differences between null, undefined, and undeclared?

JavaScript Basic

Explain event delegation, capturing, and bubbling in the browser

Browser Internals Intermediate

What is the difference between e.target and e.currentTarget?

Browser Internals Basic

What is CORS and why does it exist?

Browser Internals Intermediate

Explain the HTTP caching mechanism

Browser Internals Intermediate

What are the differences between cookie, sessionStorage, and localStorage?

Browser Internals Basic

You know localStorage, but do you know IndexedDB?

Browser Internals Intermediate

What is a Web Worker and what can it be used for?

Browser Internals Intermediate

Walk through the entire process from typing a URL to seeing the page

Browser Internals Advanced

Describe the browser rendering process. What is the difference between reflow and repaint?

Browser Internals Intermediate

What is the difference between HTTP and HTTPS?

Browser Internals Basic

What are cookie attributes? How to prevent JS from accessing cookies?

Browser Internals Intermediate

What are the differences between HTTP/1, HTTP/1.1, and HTTP/2?

Browser Internals Intermediate

What is a CDN?

Browser Internals Basic

What are the differences between TCP and UDP?

Browser Internals Basic

What are the common HTTP status codes?

Browser Internals Basic

What are the data types in JavaScript? How do you identify a variable's data type?

JavaScript Basic

What are the differences between Set, Map, WeakSet, and WeakMap?

JavaScript Intermediate

What are the differences between Map and Object? Why use Map when Object exists?

JavaScript Intermediate

What are the differences between var, let, and const in JavaScript?

JavaScript Basic

What is strict mode (use strict)? What are its benefits?

JavaScript Basic

What is Hoisting in JavaScript?

JavaScript Basic

JavaScript Array Iteration Methods (for loop, for...in, for...of, forEach, map, filter, every, some)

JavaScript Basic

How do you calculate the average of an array in JavaScript?

JavaScript Basic

What are Scope and Scope Chain in JavaScript?

JavaScript Intermediate

What are the differences between ==, ===, and Object.is() in JavaScript?

JavaScript Basic

Explain the value of 'this' in JavaScript

JavaScript Intermediate

What is a Higher-Order Function?

JavaScript Basic

What is an IIFE (Immediately Invoked Function Expression) in JavaScript? What are the pros and cons?

JavaScript Basic

What are the differences between arrow functions and regular functions in JavaScript?

JavaScript Basic

In JavaScript, does sort with (a,b) ⇒ b - a produce ascending or descending order? Why?

JavaScript Basic

What is ES6 class? How does it differ from function constructors?

JavaScript Intermediate

What is Promise.all? Please implement Promise.all

JavaScript Intermediate

How do you use call, apply, and bind in JavaScript?

JavaScript Intermediate

What is a Promise in JavaScript? What is it used for?

JavaScript Intermediate

What is Promise.race()? How do you implement it?

JavaScript Intermediate

What is the difference between shallow copy and deep copy in JavaScript? How do you implement them?

JavaScript Intermediate

What are the new features in ES2023?

JavaScript Basic

Implement array flattening (flatten)

JavaScript Intermediate

Why is structuredClone recommended for deep copying in JavaScript?

JavaScript Intermediate

What are the new features in ES6?

JavaScript Basic

How does v-model work under the hood?

Vue 3 Intermediate

What is the difference between v-if and v-show?

What are Vue's lifecycle hooks?

How does Vue implement reactivity?

Vue 3 Intermediate

What is the difference between computed and methods in Vue?

What is the difference between ref and reactive in Vue 3?

Vue 3 Intermediate

What are Vue Router navigation guards?

Vue 3 Intermediate

What is the difference between Pinia and Vuex?

Vue 3 Intermediate

How do parent and child components communicate in Vue?

Can you tell me about yourself?

Behavioral Interview Basic

API Rate Limiting Algorithms and Distributed Throttling

categories.api-design Intermediate

Have you ever had a disagreement with a colleague or manager? How did you handle it?

Behavioral Interview Basic

Tell me about a challenge you faced and how you overcame it

Behavioral Interview Basic

Why do you want this role? Why our company?

Behavioral Interview Basic

What are your career goals for the next 3 to 5 years?

Behavioral Interview Basic

What is a DDoS Attack? How do you defend against it?

Network Security Basic

What is SQL Injection? How do you prevent it?

Network Security Basic

Distributed Lock Design and Implementation

categories.system-design Advanced

What is a CSRF Attack? How do you prevent it?

Network Security Basic

What is an XSS Attack? How do you prevent it?

Network Security Basic

How do database indexes work? How do you decide which columns to index?

categories.database Intermediate

What are common caching strategies? Explain Cache-Aside, Write-Through, and Write-Behind.

categories.performance Intermediate

API Gateway: Role and Core Functions in Microservices

categories.api-design Intermediate

WebSocket vs Long Polling vs SSE: Differences and Use Cases

categories.api-design Intermediate

What Is API Idempotency and How Do You Design Idempotent APIs?

categories.api-design Intermediate

API Pagination Design: Offset vs Cursor-based Pagination

categories.api-design Intermediate

How Does the Node.js Event Loop Work? How to Avoid Blocking?

categories.language Intermediate

Concurrency vs Parallelism: What Is the Difference?

categories.language Basic

What Do SOLID Principles Stand For? Can You Give Examples?

categories.language Intermediate

What Are the Core Concepts of Memory Management and Garbage Collection?

categories.language Intermediate

What Are the Most Common Design Patterns in Backend Development?

categories.language Intermediate

Static vs Dynamic Typing: Differences and When to Use Each

categories.language Basic

Backend Language Selection: Node.js, Python, Go, or Java?

categories.language Basic

What Are ACID Properties? What Does Each Letter Mean?

categories.database Intermediate

What Is the N+1 Query Problem? How to Detect and Fix It?

categories.database Intermediate

Database Sharding Strategies: Types and Trade-offs

categories.database Advanced

What Is the CAP Theorem? How to Apply It in System Design?

categories.database Intermediate

What Are the Four Transaction Isolation Levels and What Problems Do They Solve?

categories.database Advanced

What Is Database Normalization? Differences Between 1NF, 2NF, and 3NF

categories.database Basic

Message Queue Use Cases and Technology Selection (Kafka vs RabbitMQ)

categories.system-design Intermediate

Load Balancing Strategies: Algorithms and L4 vs L7 Differences

categories.system-design Intermediate

Circuit Breaker Pattern: How It Works and Implementation

categories.system-design Intermediate

Distributed Cache Design: Redis's Role in System Architecture

categories.system-design Intermediate

Microservices vs Monolith: How to Choose the Right Architecture

categories.system-design Intermediate

Saga Pattern for Distributed Transactions

categories.system-design Advanced

SQL Injection Attack and Prevention

categories.security Basic

XSS Cross-Site Scripting Attack and Defense

categories.security Basic

CSRF Cross-Site Request Forgery and Defense

categories.security Intermediate

JWT Best Practices and Security Considerations

categories.security Intermediate

Password Hashing Best Practices: bcrypt vs Argon2

categories.security Basic

HTTPS and TLS Encryption

categories.security Basic

Authentication vs Authorization

categories.security Basic

Database Query Optimization Strategies

categories.performance Intermediate

Async Processing Patterns: Message Queues and Background Jobs

categories.performance Intermediate

CDN Strategy and Static Asset Optimization

categories.performance Intermediate

Latency vs Throughput

categories.performance Basic

Horizontal vs Vertical Scaling

categories.performance Basic

Backend Performance Profiling Techniques

categories.performance Intermediate

SQL JOIN Types Explained

categories.sql-transformation Basic

SQL CTEs and Recursive Queries

categories.sql-transformation Intermediate

SQL Query Optimization: EXPLAIN and Execution Plans

categories.sql-transformation Intermediate

Data Pipeline Orchestration: Apache Airflow

categories.pipeline-orchestration Intermediate

ETL vs ELT: Data Pipeline Pattern Comparison

categories.pipeline-orchestration Basic

Change Data Capture (CDC)

categories.pipeline-orchestration Advanced

OLAP vs OLTP: Analytical vs Transactional Databases

categories.warehouse-modeling Basic

dbt Data Transformation Workflow

categories.warehouse-modeling Intermediate

Data Warehouse vs Data Lake vs Data Lakehouse

categories.warehouse-modeling Basic

Stream Processing: Windowing and Time Semantics

categories.stream-processing Advanced

Apache Spark Core Architecture

categories.batch-processing Intermediate

Stream Processing Message Semantics: Exactly-Once vs At-Least-Once

categories.stream-processing Advanced

Batch Processing Design Patterns

categories.batch-processing Intermediate

Spark Performance Tuning

categories.batch-processing Advanced

Data Formats: Parquet vs ORC vs CSV

categories.batch-processing Basic

MapReduce Computing Paradigm

categories.batch-processing Basic

True Streaming vs Micro-Batch Processing

categories.stream-processing Basic

Lambda Architecture vs Kappa Architecture

categories.stream-processing Advanced

Apache Kafka Core Concepts

categories.stream-processing Intermediate

Data Warehouse Partitioning and Clustering

categories.warehouse-modeling Intermediate

Dimensional Modeling: Star Schema vs Snowflake Schema

categories.warehouse-modeling Intermediate

Data Quality Monitoring

categories.pipeline-orchestration Intermediate

SQL Transactions and ACID Properties

categories.sql-transformation Basic

Data Pipeline Idempotency Design

categories.pipeline-orchestration Intermediate

SQL Window Functions

categories.sql-transformation Intermediate

What are the six dimensions of data quality?

categories.data-quality-observability Basic

What is Data Lineage and how do you track it?

categories.data-quality-observability Intermediate

How do you implement anomaly detection in a data pipeline?

categories.data-quality-observability Intermediate

What is a Data Catalog and what problems does it solve?

categories.data-quality-observability Basic

What are the five pillars of data observability? How do you build a comprehensive monitoring system?

categories.data-quality-observability Advanced

What is the difference between Docker containers and VMs? What is the relationship between Image and Container?

categories.containers-platform Basic

What are the roles of Pod, Deployment, and Service in Kubernetes?

categories.containers-platform Basic

What is the difference between Resource Requests and Limits in Kubernetes? How do you configure them?

categories.containers-platform Intermediate

What is Kubernetes Ingress? How does it differ from a LoadBalancer Service?

categories.containers-platform Intermediate

What is a Service Mesh? What problems does it solve in microservices architectures?

categories.containers-platform Advanced

What is Infrastructure as Code (IaC)? What is Terraform's core workflow?

categories.infrastructure-as-code Basic

What is Terraform State? How do you manage remote state for team collaboration?

categories.infrastructure-as-code Intermediate

What is GitOps? How does it differ from traditional CI/CD deployment?

categories.infrastructure-as-code Intermediate

What is a Terraform Module? How do you design reusable modules?

categories.infrastructure-as-code Intermediate

What is Policy as Code? How do you implement compliance controls in an IaC workflow?

categories.infrastructure-as-code Advanced

What are the key stages of a CI/CD pipeline? What is the difference between CI and CD?

categories.delivery-automation Basic

What are the common deployment strategies? What is the difference between Blue-Green and Canary deployments?

categories.delivery-automation Intermediate

How does DevSecOps integrate security into CI/CD pipelines?

categories.delivery-automation Intermediate

What are Feature Flags? How do they support continuous deployment and reduce release risk?

categories.delivery-automation Intermediate

How do you manage artifacts in CI/CD? Why are versioning strategy and immutable artifacts important?

categories.delivery-automation Basic

What are the core design principles of Cloud-Native applications?

categories.cloud-architecture Basic

How do you design a multi-region high-availability architecture? What are RPO and RTO?

categories.cloud-architecture Advanced

What are the auto-scaling strategies in cloud environments? What is the difference between horizontal and vertical scaling?

categories.cloud-architecture Intermediate

How do you optimize cloud infrastructure costs? What are common cost reduction strategies?

categories.cloud-architecture Intermediate

What are the pros and cons of Serverless architecture? When should you choose Serverless?

categories.cloud-architecture Intermediate

What are the three pillars of observability? What are Metrics, Logs, and Traces each used for?

categories.observability Basic

What are SLI, SLO, and SLA? How do you define them in practice?

categories.observability Intermediate

How does distributed tracing work? What are Span and Trace ID?

categories.observability Intermediate

How do you design an effective alerting strategy? How do you avoid alert fatigue?

categories.observability Intermediate

How does Prometheus work? How does it integrate with Grafana?

categories.observability Basic

What is the complete incident management process? What are the key elements of a Post-mortem?

categories.reliability-sre Intermediate

What is Chaos Engineering? How do you practice it safely in production?

categories.reliability-sre Advanced

What is Toil in SRE? How do you identify and reduce it?

categories.reliability-sre Basic

How does SRE approach capacity planning? What role does load testing play?

categories.reliability-sre Advanced

What are the common reliability design patterns in distributed systems?

categories.reliability-sre Intermediate