Betsy Cooper

Users of apps and sites as diverse as Venmo, Reddit, and Duolingo reported problems.

They were traced back to a failure in Amazon's cloud computing service that arose in the early hours of Monday morning.

Amazon, Microsoft, and Google are among the biggest cloud computing providers.

And while there are some benefits for companies that rely on these huge providers, cybersecurity expert Betsy Cooper says this incident highlights vulnerabilities.

And we should note, Amazon is a financial supporter of NPR, and it pays to distribute some of NPR's content.

Jacqueline Diaz, NPR News.