Amazon Simple Storage Service (S3) is a popular cloud storage service part of the Amazon Web Services (AWS). Amazon S3 cloud storage provides high reliability, flexibility, scalability and accessibility. The number of objects and the amount of data stored in Amazon S3 is unlimited. S3 cloud storage is attractive for business because you pay only for what you use. However, terminology and methodology may lead to misunderstanding and difficulties for new Amazon S3 users. Where is S3 data stored? How does Amazon S3 storage work? This blog post explains the main concepts and working principle of Amazon S3 cloud storage.