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What is Amazon S3?

amazon s3
(Image credit: Photo by Ian Battaglia on Unsplash)


First launched in 2006, the Amazon Simple Storage Service (Amazon S3) is a platform designed to simplify large scale computing for IT teams by making secure and scalable object storage easy to access through a user-friendly web services interface. 

Today, Amazon S3 is a core part of Amazon Web Services (AWS) and the internet as a whole. AWS provides an estimated 40% of the world’s cloud storage capacity and thousands of corporations and apps, including big names like Netflix and Airbnb, rely on it to store important files. Because of this, much of the modern web simply wouldn’t work without S3.

To really see why S3 matters and understand what this service does, we need to start with the idea of object storage. Traditional file systems manage data according to strict hierarchical rules where one piece of information is related to another, meaning data can only be accessed if you know what the rules are. This works great for specific applications but makes it very tricky to store information of different types in the same database.

By contrast, S3 is an object storage system whereby blocks of data are saved independently as objects. Each object can contain multiple information formats, including metadata and identifiers, which gives object-based systems big advantages over traditional alternatives when it comes to flexibility, reliability, and speed.

As Amazon S3 is a cloud service and available through a web services interface, you can access data uploaded to it from anywhere in the world. You can transfer a file to S3 by first creating an S3 bucket in any one of Amazon’s global regions and then uploading to it. Buckets are what Amazon calls its fundamental containers for S3 data, and each one can contain an infinite number of objects of up to 5 TB in size. To make it secure and reliable, Amazon intentionally designed S3 as a minimalist system, but you can grant permissions for each bucket to decide who is able to upload or download data from it.

When businesses are managing a large volume of data through Amazon S3, they don’t simply use the S3 web services interface. Instead, they manage S3 bucket data through application programming interfaces (APIs) and via the Amazon S3 console. The S3 API can be used to retrieve, store, and delete S3 objects. One of the reasons that S3 has become so popular is that integrating S3 API commands into other platforms is straightforward because each object can be accessed through a URL containing the object name, bucket name, and relevant AWS region.

Another reason that so many online businesses have made S3 part of their tech backbone is that it offers what Amazon calls the 11 nines of reliability. Like Microsoft Azure and a handful other industry-leading cloud storage providers, S3 has a 99.999999999% uptime rate, making it suitable for mission-critical applications.

Benefits of Amazon S3

Amazon S3 shares many benefits with other cloud storage services, and one of these is scalability. Similarly to a regular hard drive, S3 buckets can be used for traditional storage for everyday files (documents, multimedia content, etc.), and anyone can begin using S3 for free and take advantage of its object storage service to build a quick app in a couple of hours. It doesn’t cost anything to store 5GB of S3 data for a year, though caps are put on the amount of information you can download each month and the number of data manipulation requests you can make. 

At the other end of the spectrum, Amazon S3 can scale up to provide high-level functionality for large operations. S3’s virtually infinite storage capacity enables developers to create data lakes for advanced visualization, reporting, and analytics. For this reason, social media networks like Facebook, research institutions, and high-tech manufacturers such as Ford all use Amazon S3 for data storage and modeling tasks. 

There’s plenty of middle ground, too. Lots of small startup businesses choose to use Amazon S3 to save cash instead of purchasing their own IT equipment. S3 can be integrated with an existing IT infrastructure, but you don’t need to have one to use it. This means that many startups begin life using the lowest tier of S3 object storage allocations but increase their capacity on the fly as they experience growth. 

What’s more, because S3 integrates with other AWS products like Amazon Cloudfront (for secure content distribution) and Amazon Glacier (backups), there’s no need to worry about managing your own servers even as your business grows and your data requirements change. At no point will you need to suddenly migrate to a dedicated server system. 

To put it briefly, S3’s absurdly large storage capacity, scalability, and durability have made this platform a vital part of the modern internet. It’s not surprising that large-scale web apps like Pinterest, Reddit, and Dropbox are reliant on it. Without S3, these and numerous other social media platforms, e-commerce stores, and mobile apps might not exist at all.