What is IGW?

IGW most commonly refers to an Internet Gateway in cloud computing environments like Amazon Web Services (AWS). An Internet Gateway is a horizontally scaled, redundant, and highly available VPC component that allows communication between instances in your VPC and the internet. It serves two purposes: it provides a target in your VPC route tables for internet-routable traffic, and it performs network address translation (NAT) for instances that have been assigned public IPv4 addresses. It is typically used to allow EC2 instances in a private subnet to access the internet for updates or other external services, and for instances in a public subnet to be directly accessible from the internet.