The term refers to a file format utilized by Apple for installing or restoring the operating system on its iOS devices, specifically for the anticipated eighteenth major release. These files contain all the necessary components for a complete system installation, including the operating system, firmware, and device drivers. As an example, a developer might use this type of file to install a beta version of the forthcoming system software on a test device.
Its significance lies in its role as the primary method for updating or restoring the operating system on compatible iPhones and iPads. Benefits include the ability to perform clean installations, revert to previous versions, and troubleshoot software issues. Historically, these files have been crucial for both end-users and developers in managing the software on Apple’s mobile devices, allowing for greater control and flexibility compared to over-the-air updates alone.