The article delves into the process of how containers in Docker gain internet access upon creation. The network abstractions involved include the creation of a virtual bridge network, docker0, which serves as the default gateway for containers on the host. Through NAT and masquerading, Docker translates internal container IPs into the host machine’s IP for outbound connectivity. iptables plays a crucial role in filtering packets, applying NAT rules, and ensuring container isolation, all managed automatically by Docker at the kernel level. Understanding these underlying mechanisms is essential for DevOps engineers and technologists working with containerized environments.