An emulator recreates the functionality of a specific hardware or software system within another environment. While emulators themselves don't directly open files, you can use them to launch legacy or specialized applications (like a game console operating system, an old web browser, or vintage productivity software) that can natively open certain file types. This process mimics running the original system that understood those files, unlike a standard viewer or editor.

For instance, a Super Nintendo Entertainment System (SNES) emulator can run game cartridges (ROM files). Similarly, an emulator for an old Apple II computer can run software designed for that system, allowing you to open files like AppleWorks documents (.cwk) or specific game saves that the original hardware could process. This is common in digital preservation, retro computing, and gaming communities.

Using emulators for file access preserves data trapped in obsolete formats, which is crucial for archives and research. However, it requires obtaining or recreating the original application software capable of opening the file within the emulated environment. Significant technical complexity may be involved in setting up the emulator correctly and finding compatible software. Legal considerations around software copyright and ROM ownership also apply, especially for games.