Pulumi is a tool that lets regular developers write simple code to create and manage their cloud servers, databases, and other resources instead of clicking around in complicated web dashboards. In everyday terms, it works like a recipe book where you write instructions in your favorite programming language and it automatically builds and updates everything you need in the cloud. It stores the current picture of all your cloud resources as simple files in S3-compatible object storage so it always knows exactly what exists and what needs to change. Every time you update your code, Pulumi compares the new plan against the previous snapshot saved in S3 to figure out only the necessary changes, making updates fast and safe. This clever use of everyday S3 storage means teams can safely collaborate, roll back mistakes easily, and track their entire cloud setup over time without needing expensive extra databases. Pulumi lets software developers build and manage massive cloud systems just by writing code, it supports S3-compatible backends for state management, snapshots, and secure multi-user collaboration.