[1] Like all virtual appliances, the main component of an AMI is a read-only filesystem image that includes an operating system (e.g., Linux, Unix, or Windows) and any additional software required to deliver a service or a portion of it.
An XML manifest file stores information about the AMI, including name, version, architecture, default kernel id, decryption key and digests for all of the filesystem chunks.
[5] When it launched in August 2006, the EC2 service offered Linux and later Sun Microsystems' OpenSolaris and Solaris Express Community Edition.
[6][7] As of December 2010, it has also been reported to run FreeBSD;[8] in March 2011, NetBSD AMIs became available.
[15] Amazon Linux 2023 was the next version, which launched alongside a new two-yearly release cadence.