An instance is a specific running copy of a resource, such as a virtual machine, container, or object in memory. In cloud computing, instances refer to compute units created from machine images. In programming, an instance is an object created from a class. Instances can be configured, started, stopped, and scaled based on application needs.
Why it matters
Instances represent the actual compute or memory resources your application uses. Understanding instances helps optimize costs, scale workloads, and diagnose system behavior. Instances also form the foundation of cloud services.
Examples
Launching an EC2 instance in AWS or creating an instance of a Python class with User().