So far we have been working out of a single AWS account that we use for development, testing as well as for production purposes, but this isn't the case with many organizations who end up with multiple AWS accounts for a variety of purposes such as multiple environments, compliance issues, and so on. Each account gets governed and managed in its own way with no centralized ownership or control.
AWS Organizations is a simple service that allows you to consolidate and manage multiple such AWS accounts all under one roof. It enables you to group AWS accounts into one or more collective organizations that you can create and manage as a whole.
Here's a quick look at some of AWS Organizations key concepts and terminologies: