Container

A container is like a VM’s cooler, leaner cousin. It packages your application with its dependencies into an isolated unit that shares the host OS kernel. No guest OS overhead, no bloated disk images — just your app and what it needs.

Containers start in milliseconds (not minutes), use a fraction of the memory of VMs, and run identically across environments. They’re the building blocks of modern cloud-native architecture.

Why it matters: Containers solved the “works on my machine” problem and enabled microservices architecture. They’re the atoms of modern infrastructure.