Today, we renamed AWS Certificate Manager Private Certificate Authority to AWS Private Certificate Authority (AWS Private CA). This change helps customers differentiate between AWS Certificate Manager (ACM) and AWS Private CA. ACM and AWS Private CA have distinct roles in the process of creating and managing the digital certificates used to identify resources and secure network communications over the internet, in the cloud, and on private networks. ACM manages the lifecycle of certificates: creating, storing, deploying, and managing renewals for AWS services such as Elastic Load Balancing, Amazon CloudFront, and Amazon API Gateway. AWS Private CA enables customers to create customizable private certificates for a broad range of scenarios. AWS services such as ACM, Amazon Managed Streaming for Apache Kafka (MSK), IAM Roles Anywhere and Amazon Elastic Kubernetes Service (EKS) can all leverage private certificates from Private CA. It also supports creating private certificates for Internet of Things (IoT) devices as well as enterprise users, systems and services.
Source: AWS