A Container Runtime is a server software that executes and manages Containers on a single host system. It assigns requested resourced, sets up local network configuration and ensures that individual container executions are isolated from each other.
The industry-wide agreed upon standard for Container Runtimes is the Open Container Initiative (OCI) runtime specification. Every runtime that implements it is able to run Containers that comply with the OCI image specification.
The most popular Container Runtime is Containerd, followed by runc, LXC, Docker Engine and more.
Under Linux Container Runtimes use namespaces to isolate the network, filesystem access and process table, as well as Cgroups to isolate the CPU, memory, swap and disk i/o.
