What Is AWS S3? A Complete Guide to the Simple Storage Service

Headshot of CareerFoundry contributor Alex Williams.

Millions of people and thousands of companies use AWS cloud computing technology every day. 

But among the most effective and valuable tools in the AWS package is S3, a unique program that allows individuals to store and protect data objects and buckets in the cloud.

In this article, let’s break down AWS S3 in detail and learn what it is, how to use it, and its benefits for businesses.

If you’re already familiar with a topic, feel free to skip ahead by using the clickable menu:

  1. What is AWS cloud computing?
  2. What is S3 in AWS?
  3. What is an AWS S3 object?
  4. What is an AWS S3 bucket?
  5. How to learn more about AWS S3 and cloud computing

1. What is AWS cloud computing?

AWS or Amazon Web Services cloud computing is an intuitive, accessible, and easy-to-use cloud platform that offers various services on demand. Thus, it’s a perfect tool for both individuals using its free tier as well as growing businesses.

AWS cloud computing offers file storage, through which employees can access important files from anywhere they have an internet connection, as well as computing resources for businesses that don’t have the money to build their own servers just yet.

Many small businesses on a tight budget are often forced to rely on securing loans to afford to pay for basic business expenses including building their own servers for storing data, but even the average business loan may not be enough to cover the costs when other business expenses are factored in. 

AWS offers businesses in a tight financial condition like this a more affordable option for storing their data. It also includes content delivery, application access, and digital security. It’s an all-in-one cloud computing services package, and it’s used by companies worldwide.

In fact, large companies like Netflix, Facebook, and Twitch use AWS cloud computing every day. Millions of customers take advantage of AWS cloud computing’s features and resources without knowing it.

2. What is S3 in AWS?

Amazon Web Services S3, sometimes called Amazon S3, stands for Amazon Simple Storage Service. It’s one of AWS’s many programs and is designed to store, protect, and then allow customers to retrieve data from discrete buckets anytime and anywhere on any appropriate device.

For cloud engineers, knowing not just what is AWS s3 but also how to deploy it securely are key skills.

It’s a type of object-level storage that allows any datatype to be stored on Amazon’s cloud servers, enabling easy access and retrieval when necessary without compromising security. 

Put another way, AWS S3 doesn’t store any files in a file system. Instead, it converts and then stores files as digital objects

Through this object storage service, users can upload their files, documents, and videos just as they would to cloud storage systems like Dropbox or Google Drive.

As a result, S3 in AWS is flexible, platform agnostic, and highly useful for both businesses and individuals. 

A cloud developer happily working in their home office using AWS S3.

Advantages of AWS S3

There are lots of benefits to AWS S3. The first of these is scalability. Amazon S3 only charges you for the resources and storage space you use, without any overage charges or hidden fees. 

On top of that, the tool is designed for extreme durability and stability. For example, when you upload an object to S3, AWS creates and stores multiple copies of that object on different systems to protect it and enable easy access.

S3 isn’t just cost-effective; it’s also highly secure (see more below). With S3, you don’t need to worry about your business files being stolen or decrypted without your authorization, let alone someone unauthorized getting access to them in the first place.

And don’t forget the object or file versioning feature, which allows you to save multiple versions of your file on the same server so you can compare performance or roll back updates if they don’t improve things as expected.

All in all, it’s clear that this is an excellent tool for businesses in need of exceptional file storage and retrieval services on the cloud. Now that you know what is AWS S3 and why it’s worthwhile, it’s time to get familiar with some of its common terms.

3. What is an AWS S3 object?

In Amazon Web Services, an “object” is any data file stored in S3. This includes videos, photos, documents, and any other file you can imagine storing in this service.

Every file object is identified using a uniquely generated key that only works in the S3 environment. The unique key serves as a marker or differentiating factor so the system can retrieve the right file at the right time.

With AWS S3, object file size is capped at 160 GB when uploading it. However, AWS does have a few tools to let you add larger files than this cap when necessary.

4. What is an AWS S3 bucket?

The other half of the Amazon S3 system is the “bucket.” When using any S3 environment, not just Amazon’s, the file objects described above need a place to go so they can be stored securely. Buckets are essentially storage containers for file objects.

How to use S3 buckets in AWS

When you make an AWS cloud account, you can create up to 100 buckets for your file storage needs.

Buckets don’t have any limit on the number of objects you can store—whether that’s 10 objects, 100, or 1000, you’re set! Amazon further allows you to request 1000 more buckets when you submit a service limit increase (though this is primarily necessary for large enterprises).

Upon creating an AWS bucket, you can choose which AWS region you wish to store it in. For example, you can cut costs and minimize latency by storing your bucket on a server in a region geographically close to your business.

All Amazon S3 buckets are globally unique. Therefore, no AWS account in the same region can use the exact same bucket names as your buckets unless you delete them first and vice versa. In this way, Amazon S3 allows for accurate, organized, and easy file storage and retrieval no matter what.

S3 buckets and data security

S3’s buckets are incredibly beneficial for businesses and individuals alike, thanks to AWS’s encryption features and various access management tools.

All the data you store on Amazon S3 will be encrypted from the get-go, making it hard for any hacker or other cybercriminal to know what the files contain, even if they were to acquire them.

More importantly, the access management tools enable you to control who has access to files and prevent unauthorized access at any time. For example, you can block any public access from your objects (both at the account and the bucket level). Or you can assign users within your organization access to specific S3 buckets or objects.

AWS’s security features further come into play with S3 buckets. For example, you can take advantage of multi-factor authentication whenever an object is meant to be edited or deleted. The same is true when editing or deleting a bucket. However, be careful—misconfigured S3 buckets are one of the most frequent AWS security pitfalls made.

As a business owner, you can use AWS tools to analyze bucket access policies, make changes as necessary, and expand permissions to new workers you trust. Bottom line: S3 bucket data security, and the way it encourages good digital citizenship among employees, is top tier.

A cloud engineer teaches her colleagues in an office about AWS S3 security.

5. How to learn more about AWS S3 and cloud computing

Whether you run a small to medium-sized business or are working in a large enterprise, odds are you can take advantage of this service.

As a result, then, if you plan to work designing or maintaining their services on the cloud, you’re going to need to know what is AWS S3. But to maximize the effectiveness of these tools, you need to know more about them and cloud computing as a whole.

CareerFoundry’s Cloud Computing for developers course is a great way to start getting to grips with not just S3 and the Web Services platform, but cloud computing in general.

Starting with the fundamentals of the cloud, you’ll gain hands-on practical experience with some widely-used AWS tools, such as EC2, the VPC, Lambda, and Identity and Access Management (IAM), as well as AWS security best practices.

Offering developers a basic to intermediate level of deploying web applications on AWS cloud services, this mentored course can be taken by itself, or as part of the Full-Stack Development Program.

If you’d like to learn more about Amazon Web Services and programming in general, we have a host of guides and tutorials many more topics. Just check out these:

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