What is the purpose of instance metadata in AWS?

Instance metadata in AWS serves the critical role of providing information about the configuration and management of the running instance. This metadata is accessible from within the instance itself and includes details such as the instance ID, instance type, security groups, and other parameters that are essential for the administration and operation of the instance.

By accessing instance metadata, applications running on the instance can dynamically retrieve this information, allowing them to adjust their behavior based on the context of the instance. For example, an application may use the instance type to determine how much computational power it can expect and adjust its workload accordingly.

Additionally, since instance metadata can also include information on the associated IAM roles, it plays a crucial role in helping instances authenticate to other AWS services, thereby enhancing security and access management.

The other choices, while related to AWS, focus on aspects that do not fully capture the primary function of instance metadata. Storing user data generally refers to persistent storage solutions like Amazon S3 or Elastic Block Store, managing IAM roles is more about security and access management at a broader level outside the instance's immediate context, and monitoring network traffic pertains to services such as AWS CloudWatch and VPC Flow Logs rather than metadata itself.