Learning Amazon S3: Buckets, Objects, Storage Classes & Permissions

Muhammad Waleed — Mon, 14 Sep 2026 14:09:33 +0000

As part of my Cloud Computing learning journey, I recently explored Amazon Simple Storage Service (Amazon S3) and got hands-on experience working with cloud-based object storage.

This session helped me understand not only how files are stored in the cloud, but also how access, cost, lifecycle, and availability of those files can be managed.

What is Amazon S3?

Amazon S3 is an object storage service provided by AWS.

Instead of thinking about storage only in terms of traditional folders and disks, S3 mainly works with:

Buckets — containers used to store data
Objects — files and their associated metadata stored inside buckets
Keys — identifiers used to locate objects inside a bucket

During the practical session, I created/worked with an S3 bucket and uploaded a file as an object.

📸 I have included a screenshot from my AWS S3 practical where I uploaded a file to the bucket.

1. S3 Buckets and Objects

A bucket acts as the main container for objects.

For example:

my-cloud-bucket

could contain objects such as:

images/profile.jpg

documents/report.pdf

website/index.html

This helped me understand how cloud object storage differs from the traditional file-storage approach.

2. Uploading Objects to S3

One of the hands-on parts of the session was uploading a file to an S3 bucket.

When uploading an object, different settings can be applied, including:

Storage class
Permissions
Metadata
Encryption-related settings
Object management configurations

Working directly with the AWS console made these concepts much easier to understand.

3. S3 Storage Classes

Not every file needs the same type of storage.

AWS provides multiple S3 storage classes for different access patterns and cost requirements.

Some important examples include:

S3 Standard
S3 Intelligent-Tiering
S3 Standard-IA
S3 One Zone-IA
S3 Glacier Instant Retrieval
S3 Glacier Flexible Retrieval
S3 Glacier Deep Archive

The main idea I learned is:

The way data is accessed should influence how it is stored.

Frequently accessed data and long-term archival data should not necessarily use the same storage strategy.

4. S3 Intelligent-Tiering

One concept I found particularly interesting was S3 Intelligent-Tiering.

It is designed for data whose access pattern is changing or difficult to predict.

Instead of manually deciding where every object should remain, S3 can monitor access patterns and automatically move eligible objects between different access tiers.

This can help optimize storage costs without requiring constant manual management.

5. Bucket Policies and Permissions

Storing data is only one part of cloud storage.

Controlling who can access that data is equally important.

I learned about S3 Bucket Policies, which can be used to define permissions for a bucket and its objects.

Bucket policies use JSON-based policy rules and can specify things such as:

Who can access a resource
Which actions are allowed
Which resources the rule applies to
Conditions under which access should be permitted or denied

This introduced me to an important cloud principle:

Access should be granted intentionally and with the minimum permissions required.

6. ACLs — Access Control Lists

We also discussed Access Control Lists (ACLs).

ACLs are another mechanism that can control access to S3 buckets and objects.

However, an important point from current AWS best practices is that ACLs are disabled by default for modern S3 buckets using the Bucket owner enforced setting.

For most modern use cases, access is better managed using IAM and bucket policies.

Learning both approaches is still useful because ACLs can appear in existing systems and specific use cases.

7. S3 Lifecycle Rules

Another useful concept was Lifecycle Configuration.

Lifecycle rules allow us to automatically manage objects as they become older.

For example, a lifecycle strategy could:

Keep a new object in frequently accessed storage.
Move it to a cheaper storage class later.
Archive it when it is rarely needed.
Eventually expire/delete it when it is no longer required.

This is especially important when managing large amounts of cloud data because storage decisions directly affect cost.

8. S3 Versioning

S3 Versioning allows multiple versions of an object to be retained.

For example, suppose I upload:

report.pdf

and later upload an updated file using the same object key.

With versioning enabled, S3 can preserve previous versions rather than simply losing the earlier copy.

This can be useful for recovering from:

Accidental overwrites
Unwanted changes
Accidental deletion

Versioning showed me how cloud storage can provide an additional layer of data protection.

9. Static Website Hosting

Amazon S3 can also be used to host static website content.

Static websites usually consist of files such as:

HTML
CSS
JavaScript
Images

These files can be stored as objects and served to users.

However, S3 itself does not execute traditional server-side application logic such as PHP, Node.js server code, Django, or database-backed backend processing.

That leads to an important distinction.

Static vs Dynamic Websites

Static Website

Content is mainly delivered from pre-existing files.

Example:

HTML + CSS + JavaScript

Suitable examples include:

Portfolio websites
Documentation
Landing pages
Simple front-end applications

Dynamic Website

Content can be generated or changed by backend logic.

It may involve:

Application servers
APIs
Databases
Authentication
Server-side processing

For a complete dynamic cloud application, S3 can still store static assets, while other cloud services handle the backend.

What I Learned From This Session

This session gave me a much clearer understanding of how cloud storage goes beyond simply uploading files.

I learned how Amazon S3 combines:

Storage + Access Control + Cost Optimization + Automation + Data Protection

The topics I explored included:

Buckets and objects
File uploads
S3 storage classes
Intelligent-Tiering
Bucket policies
Permissions and ACLs
Lifecycle rules
Versioning
Static website hosting
Static vs dynamic architectures

This was another step forward in understanding how real cloud infrastructure is designed and managed.

I am looking forward to exploring more cloud services and building increasingly practical cloud projects as I continue this journey.

aws #cloudcomputing #amazonS3 #cloud #devops

DEV Community: Muhammad Waleed