A boot environment is a bootable instance of the Oracle Solaris operating system image along with any other software packages installed in that image. You can maintain multiple boot environments on your systems, and each boot environment can have different software versions installed. You can backup the current boot environment, you can update software without any risk of loss of data or the system environment. You can also update a boot environment that is currently not active. Use the beadm(1M) utility to create and manage boot environments.
See Creating and Administering Oracle Solaris 11.2 Boot Environments for detailed information about boot environments.