Add content for containers

* Update 101-containers.md

* Update content/roadmaps/102-devops/content/105-infrastructure-as-code/101-containers.md

Co-authored-by: Kamran Ahmed <kamranahmed.se@gmail.com>

content/roadmaps/102-devops/content/105-infrastructure-as-code/101-containers.md

@@ -1 +1,9 @@
-# Containers
+# Containers
+
+Containers are a construct in which [cgroups](https://en.wikipedia.org/wiki/Cgroups), [namespaces](https://en.wikipedia.org/wiki/Linux_namespaces), and [chroot](https://en.wikipedia.org/wiki/Chroot) are used to fully encapsulate and isolate a process.  This encapsulated process, called a container image, shares the kernel of the host with other containers, allowing containers to be significantly smaller and faster than virtual machines.
+
+These images are designed for portability, allowing for full local testing of a static image, and easy deployment to a container management platform.
+
+<ResourceGroupTitle>Free Content</ResourceGroupTitle>
+<BadgeLink colorScheme='yellow' badgeText='Read' href='https://cloud.google.com/learn/what-are-containers'>What are Containers?</BadgeLink>
+<BadgeLink colorScheme='yellow' badgeText='Read' href='https://www.docker.com/resources/what-container/'>What is a Container?</BadgeLink>