Video Game Emulators: What You Need to Know

Play your favorite retro games on PC

Retro video games on display.

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In the world of gaming, an emulator is a piece of software or hardware that emulates, or imitates, a video game console. With a video game emulator and the appropriate ROM or ISO files, it's possible to play retro Nintendo, Sega, and Sony games on your computer.

Information in this article applies broadly to all video game emulators. There are other types of emulators for different types of hardware.

A History of Video Game Emulators

Video game emulators became popular in the 1990s with the rise of personal computers and the web, which allowed aspiring developers to work together and create software capable of emulating their favorite game consoles like the Atari 2600 and the Nintendo Entertainment System.

The goal of emulation is generally to match the experience of using the original hardware, but many game emulators include extra features like options to integrate cheats, take screenshots, and create save states. Emulators also make it possible to play homebrew games, or games designed by fans.

Most emulators today are still made by hobbyist developers, but major companies like Nintendo have started cashing in on the retro game craze by releasing emulators for their own systems like the NES Classic and the SNES Classic.

What Are Video Game ROMs?

To play a game on a console emulator, you also need a copy of the original game file, which is typically stored in the ROM (read-only memory) format. ROM files are obtained by using special hardware that downloads data from a cartridge to a computer. For disc-based consoles like the PlayStation, game data is downloaded as an ISO image using an optical drive.

Why Do People Use Game Emulators?

Even with the increased availability of video games, obtaining physical copies of old games can be difficult and expensive. Consequently, using emulators and ROMs is the only way to play many classic titles.

Programmers even modify ROM files to change the default language so they can play games that weren't released locally. For example, the only way to play the original version of Final Fantasy III in English is to use a fan-translated ROM.

As with most software, console emulation programs are OS-specific. Fortunately, there are emulators for Linux, Windows, and Mac.

How Do Video Game Console Emulators Works?

There are multiple methods of emulation. For example, it's possible to build a device that's identical to the original hardware, or you could create a program that utilizes a computer's hardware to behave like the console.

The latter method can be extremely taxing, even on a PC that's exponentially more powerful than the original console. Consequently, creating an emulator that runs smoothly and reliably requires a lot of trial and error to iron out all of the bugs. Most older consoles can now be emulated flawlessly, but emulators for newer systems like the Xbox 360 or the Sony PSP tend to lag behind their real-life counterparts in terms of performance.

Any video game console can theoretically be emulated, but there are several limitations. Most notably, console developers carefully guard the specifics of their hardware. Although companies have been making knock-offs of popular game consoles since the dawn of the industry, major developers have become more protective of their intellectual property over time.

Are Emulators Legal?

Using emulation software to play a video game you've already purchased is perfectly legal; however, downloading ROMs for games you don't own a copy of is technically illegal in the U.S.

That said, there's no shortage of places where you can download emulators and ROMs from the internet. The emulation scene is far too big for game companies to shut it down, which is why they've started re-releasing their old games and consoles.