What is the purpose of an internet gateway in a VPC?

An internet gateway (IGW) serves as a horizontally scaled, redundant, and highly available VPC component that allows communication between instances in your VPC and the internet. It provides a target for internet-routable traffic in your VPC route tables and performs network address translation (NAT) for instances that have public IPv4 addresses. Creating a VPN connection to the VPC is handled by a Virtual Private Gateway or AWS Site-to-Site VPN. Enforcing bandwidth limits on internet traffic is not a primary function of an internet gateway; this would typically be managed through network ACLs, security groups, or other network appliances. Distributing incoming internet traffic across Amazon EC2 instances is the role of a load balancer, not an internet gateway.