A portable application (portable app), sometimes also called standalone, is a program designed to run on a compatible computer without being installed in a way that modifies the computer’s configuration information. This type of application can be stored on any storage device, including internal mass storage and external storage such as USB drives and floppy disks – storing its program files and any configuration information and data on the storage medium alone. If no configuration information is required a portable program can be run from read-only storage such as CD-ROMs and DVD-ROMs. Some applications are available in both installable and portable versions.
Like any application, portable applications must be compatible with the computer system hardware and operating system.
Depending on the operating system, portability is more or less complex to implement; to operating systems such as AmigaOS, all applications are by definition portable. Portable apps are distinct from software portability, source code written to be compilable into different executable programs for different computing platforms.
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