1. The document discusses immutable infrastructure and microservice architecture. It describes how service containers like Docker enable immutable infrastructure by allowing services to be replaced each time they are upgraded, bringing them back to a known initial state.
2. Microservice architecture involves breaking applications into independently deployable services organized around business capabilities. This allows each service to use its own programming language and data store. Service containers help address concerns around development, operations, data stores, configuration, and observability for microservices.
3. Examples of tools that can be used to implement immutable infrastructure and microservice architecture include Docker for containers, Kubernetes/Mesos for orchestration, Consul/Etcd for service discovery and configuration, and ELK/Graphite