Monday’s Amazon Web Services outage wasn’t just another tech hiccup.

It was a stark – and for many people, incredibly frustrating – reminder of how fragile our digital world has become. The outage impacted millions of users globally, including in Australia, knocking over everything from Snapchat to banking apps, from Fortnite to Tinder, from Ring doorbells to cryptocurrency exchanges. Amazon’s own website and its voice assistant Alexa were crippled.

For hours, vast swaths of the internet simply vanished.

An AWS outage has crippled the global internet.Credit: Nathan Perri

Amazon’s internal systems also went offline, with warehouse workers reportedly told to stand by in break rooms, while their pay app stopped working.

The culprit was a problem with Amazon Web Services, the cloud computing unit of tech giant Amazon. To understand why this matters, it’s important to clarify what the “cloud” actually is.

Despite the ethereal name, the cloud is really just someone else’s computer. Specifically, massive warehouses full of servers that companies rent to run their websites and apps instead of buying their own equipment. Two decades ago, many companies had their own data centres and servers. That’s not the case any more.

Cloud computing – and therefore the websites and apps we all rely on every day – has become dangerously concentrated in the hands of a few tech giants.

Amazon Web Services is the world’s largest provider of these rented computers, controlling roughly 30 per cent of the global market, with Microsoft and Google holding another 33 per cent between them.

Australia is particularly reliant on AWS. The federal government inked a

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