[Most Asked] AWS Basic Interview Questions 2025

Friends Are you preparing for an AWS (Amazon Web Services) interview in 2025? If so, you’re in the right place! AWS is one of the most popular cloud computing platforms, and many companies use it to store data, run applications, and manage websites.

In this article, we will cover the most asked AWS basic interview questions 2025 in a simple and easy-to-understand way. Whether you are a beginner or just want to refresh your knowledge, these questions will help you feel more confident for your interview.

AWS basic Interview Questions And Answers

1. What is AWS?

Answer: AWS (Amazon Web Services) is a cloud computing platform by Amazon that provides services like storage, computing power, and databases over the internet.

📌 Explanation: AWS helps companies run websites, store files, and process data without buying expensive hardware.

2. What are the key services of AWS?

Answer: The main AWS services include:

• EC2 – Virtual servers
• S3 – Storage service
• RDS – Database service
• Lambda – Serverless computing
• VPC – Virtual network

📌 Explanation: These services help businesses run applications, store data, and connect networks easily.

3. What is EC2 in AWS?

Answer: EC2 (Elastic Compute Cloud) provides virtual machines (VMs) to run applications on the cloud.

📌 Explanation: Instead of buying physical servers, you can use EC2 to rent computing power as needed.

4. What is S3 in AWS?

Answer: S3 (Simple Storage Service) is an online storage service that allows users to store and retrieve data anytime.

📌 Explanation: S3 is like an online hard drive where you can save files, images, and videos securely.

5. What is IAM in AWS?

Answer: IAM (Identity and Access Management) is a service that controls user access to AWS resources.

📌 Explanation: It helps manage permissions, ensuring only authorized users can access AWS services.

6. What is an AWS Region?

Answer: An AWS Region is a geographical area where AWS has data centers.

📌 Explanation: AWS has multiple regions worldwide to provide faster and more reliable services.

7. What is an Availability Zone in AWS?

Answer: Availability Zones (AZs) are separate data centers within an AWS Region.

📌 Explanation: Each region has multiple AZs to prevent data loss if one zone fails.

8. What is the difference between EC2 and S3?

Answer:

• EC2 is used for computing power (running applications).
• S3 is used for storing files and data.

📌 Explanation: Think of EC2 as a computer and S3 as a storage device.

9. What is AWS Lambda?

Answer: AWS Lambda is a serverless computing service that runs code without managing servers.

📌 Explanation: You upload your code, and AWS runs it automatically when needed.

10. What is a VPC in AWS?

Answer: VPC (Virtual Private Cloud) is a private network within AWS for secure communication.

📌 Explanation: It allows businesses to control network settings, like IP addresses and subnets.

11. What is an AWS Elastic Load Balancer (ELB)?

Answer: ELB distributes incoming traffic across multiple servers to prevent overload.

📌 Explanation: It ensures websites and applications run smoothly by balancing traffic.

12. What is AWS Auto Scaling?

Answer: Auto Scaling automatically increases or decreases the number of EC2 instances based on demand.

📌 Explanation: It helps save costs by running more servers during high traffic and fewer during low traffic.

13. What is Amazon RDS?

Answer: RDS (Relational Database Service) is a managed database service for storing and managing structured data.

📌 Explanation: It makes database management easy by handling backups, scaling, and security.

14. What is CloudFront in AWS?

Answer: CloudFront is a content delivery network (CDN) that speeds up website loading by caching content.

📌 Explanation: It delivers data from servers closest to users, reducing delays.

15. What are AWS Pricing Models?

Answer: AWS offers different pricing options:

1. Pay-as-you-go – Pay only for what you use.
2. Reserved Instances – Pay upfront for long-term discounts.
3. Spot Instances – Buy unused capacity at lower prices.

📌 Explanation: These models help businesses save costs based on their needs.

AWS basic Interview Questions For Freshers

16. What are the benefits of using AWS?

Answer: AWS offers scalability, cost-effectiveness, security, flexibility, and global reach.

📌 Explanation: AWS helps businesses grow without buying expensive hardware and provides secure, reliable cloud services.

17. What is the difference between Public Cloud, Private Cloud, and Hybrid Cloud?

Answer:

• Public Cloud – Services are available to everyone (e.g., AWS, Google Cloud).
• Private Cloud – Services are used by a single organization.
• Hybrid Cloud – A combination of public and private cloud.

📌 Explanation: AWS is a public cloud provider, meaning it offers services to multiple users worldwide.

18. What is an AWS Free Tier?

Answer: AWS Free Tier provides limited free services for new users to explore AWS for up to 12 months.

📌 Explanation: It allows beginners to practice AWS services without paying.

19. What is the difference between Scalability and Elasticity in AWS?

Answer:

• Scalability – Increases or decreases resources based on long-term demand.
• Elasticity – Adjusts resources automatically based on real-time traffic changes.

📌 Explanation: Scalability is planned, while elasticity happens instantly when needed.

20. What is AWS CloudFormation?

Answer: CloudFormation helps create and manage AWS infrastructure using code (Infrastructure as Code).

📌 Explanation: Instead of setting up resources manually, CloudFormation automates the process.

21. What is Amazon SNS?

Answer: SNS (Simple Notification Service) is a messaging service that sends notifications to users via email, SMS, or other applications.

📌 Explanation: It helps send alerts and updates automatically.

22. What is Amazon SQS?

Answer: SQS (Simple Queue Service) is a message queue service that helps applications communicate asynchronously.

📌 Explanation: It ensures messages are delivered even if the receiving system is temporarily unavailable.

23. What is AWS Glue?

Answer: AWS Glue is a fully managed data integration service used for extracting, transforming, and loading (ETL) data.

📌 Explanation: It helps process and prepare data for analytics.

24. What is AWS CloudWatch?

Answer: CloudWatch is a monitoring service that tracks AWS resource usage and performance.

📌 Explanation: It helps detect problems by analyzing logs, metrics, and alerts.

25. What is Amazon Route 53?

Answer: Route 53 is AWS’s Domain Name System (DNS) service used for domain registration and traffic routing.

📌 Explanation: It helps direct users to the correct website or application.

26. What is Amazon EBS?

Answer: EBS (Elastic Block Store) provides persistent storage for EC2 instances.

📌 Explanation: Even if you stop an EC2 instance, your data remains stored in EBS.

27. What is Amazon Elastic Beanstalk?

Answer: Elastic Beanstalk is a service that allows developers to deploy and manage applications easily without worrying about infrastructure.

📌 Explanation: It helps developers focus on coding while AWS handles servers and scaling.

28. What is the difference between Amazon RDS and DynamoDB?

Answer:

• RDS – A relational database service (e.g., MySQL, PostgreSQL).
• DynamoDB – A NoSQL database for fast and flexible data storage.

📌 Explanation: RDS is structured, while DynamoDB is designed for unstructured and high-speed data processing.

29. What is AWS Snowball?

Answer: AWS Snowball is a data transfer service that allows users to move large amounts of data offline using physical devices.

📌 Explanation: It helps transfer terabytes of data when internet bandwidth is slow.

30. What is AWS Shield?

Answer: AWS Shield is a security service that protects applications from Distributed Denial of Service (DDoS) attacks.

📌 Explanation: It ensures websites and applications stay online even during cyberattacks.

Also Read: Python Interview Questions for Data Analysts (With Answers and Explanations)