Caltech Bootcamp / Blog / /

Primer: What is Amazon S3?

What is Amazon S3

As anyone who lives in a house or apartment knows, you can never have too much storage. The same is true regarding your data. Fortunately, there are many cloud storage choices available. This article focuses on Amazon Web Storage’s “Simple Storage Service,” or AWS S3. If you’ve ever wondered what AWS S3 is, you’ve come to the right place!

We will review what cloud storage is, explain what AWS S3 is, how it works, its benefits, and why you should choose it. This article also covers crunchy details like objects and S3 buckets, storage classes, consoles, and AWS S3 features. Finally, we wrap things up with a brief mention of competing data storage services and a way for professionals to upskill through online cloud computing training.

So, before we answer, “What is Amazon S3?” let’s review what cloud storage is.

What is Cloud Storage?

Cloud storage is a web service where you can store, access, and quickly back up your data on the Internet. Cloud storage is more scalable, reliable and secure than conventional on-site data storage systems.

Cloud storage has two pricing models:

  • Monthly subscription, a flat rate that doesn’t reflect actual usage
  • Pay-as-you-go, where you only pay for what you use

Now, let’s find out precisely what Amazon S3 is.

What is AWS S3?

Amazon S3, or AWS S3, provides users with object storage and is created to store and recover any amount of data or information from anywhere over the Internet. AWS S3 provides this storage service via a web services interface. Although designed primarily for developers for more manageable web-scale computing tasks, AWS S3 offers users 99.999999999 percent durability and 99.99 percent object availability. AWS S3 can store computer files up to 5 terabytes.

What Are the AWS Storage Types?

Amazon Web Services S3 offers customers the following storage services:

  • S3
  • EFS
  • Storage Gateway
  • Snowball Edge
  • EBS
  • Glacier
  • Snowball
  • Snowmobile

We will be discussing storage services and storage classes more later.

Before There Was AWS S3…

Organizations had a tougher time storing, finding, and managing data. Additionally, hosting high-traffic websites, running applications, delivering content to customers, or backing up e-mails and other data files required considerable storage. It was also time-consuming and expensive to maintain the data repository systems.

Pre-cloud storage challenges included the following:

  • Purchasing hardware and software components
  • Requiring a team of trained experts to maintain the storage infrastructure
  • Data security requirements
  • No scalability options

But everything changed for the better when AWS S3 and other cloud storage providers arrived. Now, let’s talk about buckets and objects.

AWS Objects and Buckets

Objects consist of data, key (the assigned name) and metadata. Buckets are used to store objects. When a user adds data to a bucket, Amazon S3 creates a unique version ID and assigns it to the object.

Now, let’s get back to storage classes.

AWS S3 Storage Classes

Amazon S3 storage is divided into classes. Each class addresses a particular need or situation.

  • Amazon S3 Standard for frequent data access. This class is ideal for frequently accessed data, such as a student’s daily attendance records, which should be retrieved quickly.
  • Amazon S3 Standard for infrequent data access. This class is typically used where the data is long-lived and is only accessed occasionally. For example, a college student’s GPA isn’t recorded and saved every day, but if it’s needed, it’s easily obtained.
  • Amazon Glacier. Glacier is best used when the data must be archived, but high performance is optional—for instance, a student’s membership fee from ten years ago.
  • One Zone-IA Storage Class. This class is typically used when the data is accessed infrequently and is stored in a single region. For example, a student’s quarterly report card isn’t used daily and only relevant to the school, so it’s stored in a single availability region.
  • Amazon S3 Standard Reduced Redundancy Storage. This storage class is best used when the data isn’t and is reproduced quickly. For example, library books are non-critical data and can be quickly replaced if lost.

Exploring Two Significant AWS S3 Features

Amazon S3 offers two handy features that we should call out: lifecycle management and bucket policies.

Lifecycle Management

In lifecycle management, AWS S3 applies rules defining the action to a group of objects, letting the user manage and store objects cost-effectively. Lifecycle management has two types of actions:

  • Transition Action. Transactions action lets you elect to move objects to another storage class. Users can configure S3 to move data between different storage classes on a defined schedule. For example, let’s say you have data stored in the S3 standard class. If the data isn’t used frequently within 30 days, it’s moved to the S3 infrequent access class. After 60 days of low use, it’s moved to Glacier. This action helps you automatically migrate your data to lower-cost storage as it ages.
  • Expiration Actions. S3 automatically removes all objects in a bucket when a specified time or date in the object’s lifetime is reached.

Bucket Policies

A bucket policy is an IAM (identity and access management) policy that enables users to allow or deny permission to their Amazon S3 resources. Bucket policies also define security rules that apply to multiple files in a bucket. For example, if you do not want a user to access the “Wombat” bucket, then, with the aid of JSON script, you can set specific permissions that will deny unauthorized users access to that bucket.

Considering Data Protection

Amazon S3 protects the customer’s data in four ways:

  • Data Encryption. Data encryption protects data while it’s being transmitted and when at rest. This encryption is broken down into client-side encryption (data at rest) and server-side encryption (data in motion).
  • Versioning. Versioning preserves, recovers and restores early versions of objects you store in the AWS S3 bucket. Unintentional erasing or overwriting your objects can easily be rectified with versioning. For instance, it’s possible to have objects in a bucket with the same key name but different version IDs.
  • Cross-region Replication. Cross-region replication automatically copies every object uploaded to your source and destination buckets in different AWS regions. Versioning must be turned on to enable CRR.
  • Transfer Acceleration. Transfer acceleration allows fast, easy and secure file transfers over long distances between the client and S3 bucket. Transfer accelerations take advantage of worldwide edge locations provided by Amazon CloudFront, carrying data over-optimized network bridges that run continuously between the AWS Edge Location closest to the clients and your Amazon S3 bucket.

The AWS S3 Console

The AWS S3 Console inside AWS Management helps you easily manage objects and buckets. The console provides users with an intuitive, browser-based interface that lets them easily interact with AWS services.

Customers use the S3 console to create, configure and manage their buckets and to upload, download and manage their objects. The console also lets users organize storage with a logical hierarchy.

Now, it’s time to discuss the benefits of using Amazon S3.

The Benefits of AWS S3

Amazon Web Services S3 has plenty to offer users. For instance:

  • Durability. S3 provides 99.999999999 percent durability, so if you store 10,000,000 objects in AWS S3, you will only lose one single object every 10,000 years. Talk about durability!
  • Economy. S3 lets users store data in various storage classes based on file access frequency and immediacy.
  • Scalability. S3 charges customers only for what resources they actually use and no hidden fees or overage charges. Customers can quickly scale their storage resources to meet their organization’s constantly changing demands.
  • Availability. S3 offers 99.99 percent object availability.
  • Security. S3 offers a great range of access management tools and encryption features that provide quality security.
  • Flexibility. S3 is perfect for various uses such as data backup, storage, archiving, software delivery, IoT devices, disaster recovery, website hosting, mobile applications and more.
  • Simple data transfer. You don’t have to be an IT expert to transfer data on S3. The service offers simplicity and ease of use.
  • Data protection. S3 automatically creates and stores copies of every uploaded object across all your systems. This function protects your data against failures, errors and threats while guaranteeing total data availability on-demand.

So, How Does Amazon S3 Work?

So you see why AWS S3 is such a good choice, so naturally, your next question is, “Great! How does it work?” For starters, the user creates a bucket (the S3 bucket). When the bucket is created, the user specifies the region where the bucket is to be deployed. Later, when files get uploaded to the S3 bucket, the user determines the type of storage class used for those specific objects. Once the user decides on the class, they can define the bucket’s features, such as lifecycle policies, bucket policy, versioning control, etc.

Considering Competitor Services

Amazon Web Services S3 isn’t the only object software storage service. Here are some noteworthy competitive choices:

  • Alibaba Cloud Object Storage Service (OSS).
  • Azure Blob storage
  • Cloudian
  • DigitalOcean Spaces
  • Google Cloud Storage
  • IBM Cloud Object Storage
  • Oracle Cloud Infrastructure Object Storage
  • Zadara Storage

Are You Interested in Learning More About Cloud Computing?

If all this talk of cloud computing and Amazon S3 has you curious and fired up to learn more, consider this instructive, 32-week cloud computing bootcamp. Experience instructor-led, project-based, hands-on experiential learning in cloud computing and DevOps. Develop proficiency in multi-cloud strategies by learning about the Azure and AWS Cloud Platforms.

You can also check out this comprehensive cloud computing program that covers the top two cloud platforms: AWS and Azure. Hands-on industry projects will teach you how to design, plan and scale advanced cloud implementations.

According to, cloud computing professionals employed in the United States can earn an average annual salary of $94,369. Check out this valuable pair of cloud computing courses and get equipped to pursue a better career in this extremely popular field.


Q: What is Amazon S3 used for?

A: AWS S3 is used for object storage and is created to store and recover any amount of data or information from anywhere over the Internet.

Q: What does S3 stand for in AWS?

A: It stands for “Simple Storage Service.”

Q: What is the difference between EC2 and S3?

A: Amazon EC2 is a virtual server infrastructure providing resizable cloud computing capacity to run applications, host websites, and perform computing tasks, while AWS S3 is a secure, scalable cloud-based storage service for different data types and is extensively used for applications, backups, websites, and media files.

Q: What type of storage is AWS S3?

A: Amazon S3 is object storage designed to store and retrieve any amount of data from anywhere.

Q: Is S3 a protocol?

A: AWS S3 is considered an HTTP REST API in that it’s an API that employs HTTP requests that get, put, post, and delete data. Additionally, REST API is considered a “stateless” protocol, where the server doesn’t store any state regarding the client sessions on its side

Q: What is the lifecycle of S3?

A: An AWS S3 lifecycle configuration is an XML file consisting of rules set with predefined actions that the user wants Amazon S3 to perform on objects during their lifetime. Users can also configure the lifecycle using the AWS management console, AWS SDKs, REST API, and the AWS Command Line Interface (AWS CLI).

Cloud Computing Bootcamp

Leave a Comment

Your email address will not be published.

Cloud Computing Security

What is Cloud Computing Security?

Explore the fundamentals of cloud computing security in our beginner-friendly guide. Learn basic concepts important to kickstart a cloud computing career.


All About IaaS: A Comprehensive Guide

IaaS is what’s under the hood of all cloud applications and services. Learn more about what IaaS is, including its pros and cons, pricing, choosing the best provider, and more.

Cloud Computing Bootcamp


6 months

Learning Format

Online Bootcamp

Program Benefits