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What is an emulator? Everything you need to know

How much do you really know about emulators?
By
December 7, 2023
Dolphin Emulator Google Play
Joe Hindy / Android Authority

If you’re into retro gaming, odds are you’ve come across emulators. They are handy tools that allow you to play old games on your PC, gaming phone, or dedicated retro gaming handheld with ease.

So what exactly is an emulator and how does it work? We dive in to answer all of your questions, including legality and safety concerns.

What is an emulator?

An emulator is a software tool that allows a system to imitate (or emulate) the functionality of another system. This allows the host system to run software or games that were released for a different platform with completely different hardware.

There are many applications for emulators, but here’s a quick list:

  • Using software on different platforms: Software is often platform-specific, and emulators can get around this. For example, Android emulators on PC allow you to use mobile apps from your computer.
  • Development: Emulators allow developers to test software on a variety of devices to ensure the best compatibility before release.
  • Gaming: It’s unlikely that you have an NES plugged into your flat-screen OLED TV, but game emulators allow you to play classic titles from just about any device.
  • Preservation: Old software that came in formats like floppy disks or game cartridges may be inaccessible on modern devices, and emulators can help.
  • Homebrew applications: Some retro gaming enthusiasts may want to create original games for old consoles. With cartridges out of print, emulators are the only method of distribution.

How do emulators work?

Dolphin Emulator on screen controls
Joe Hindy / Android Authority

Emulators work by imitating every single piece of hardware inside the target system. This involves not just translating the target system’s machine code into something the host can understand, but also emulating things like the CPU, memory, and every other internal element.

For older devices like NES emulators and Xbox 360 emulators, this process is relatively simple. Modern computers and mobile phones are far more powerful, so it’s trivial to emulate every piece of hardware, while also adding functions like save states, increased speeds, and more.

More modern consoles are much more complicated. For example, Nintendo Switch emulators may only work for a handful of games. PlayStation 3 emulators also have notoriously poor performance due to the PS3’s unique hardware architecture. In fact, not even the PlayStation 5 can emulate the console, which is why backward compatibility isn’t available. Your only option to play these games on modern consoles is via cloud game streaming on PlayStation Plus.

Emulators can be written in different programming languages, but most often use a combination of low-level code and system-specific instructions to accurately reproduce the target system. They also require frequent maintenance to fix bugs and improve compatibility with modern architectures.

What’s the difference between an emulator and a simulator?

For developers testing software, simulators and emulators can be used to replicate devices. However, simulators merely replicate the software environment of the target device, while emulators also replicate the original hardware of the target device.

As you can imagine, simulators are much easier to develop and implement. They can be written in high-level programming languages, while emulators require a much more in-depth recreation using low-level code. Of course, the latter provides much better accuracy and allows for testing with specific CPUs and other hardware.

When it comes to gaming, simulators will not be able to run ROMs, since they only replicate the feel of the hardware, and not the hardware itself.

Are emulators legal?

GameBoy Advance with other consoles placed on a Mario magazine
Dhruv Bhutani / Android Authority

While emulators are perfectly legal, there are several gray areas surrounding their use. Emulators themselves are legal to create and distribute and are commonly used to test or preserve software. The legal main issues stem from BIOS and game ROMs.

Some emulators require specific firmware files (BIOS) from the original hardware to function. This is the case for Sega Saturn emulators, PlayStation and PlayStation 2 emulators, and many more. It is typically legal to obtain these files from a console that you own, but downloading or distributing them online is very much illegal.

The same is true for ROMs. These are essentially the software files for games, and they are required to play games on any console emulator. You can legally create these files from your own cartridges or disks, although you will likely need specific hardware adaptors to do so. Downloading and distributing ROMs is illegal in most jurisdictions around the world.

Large gaming companies, particularly Nintendo, have been very aggressively going after ROM sites. Many popular sites like Emuparadise and ROMUniverse have been forced to shut down, with fines and damages ranging in the millions of dollars.

That said, there is a case to be made when it comes to using ROMs for game preservation. Old games that are out of print run the risk of disappearing entirely and could be considered abandonware. It’s also nearly impossible to completely remove these files from the internet once they’ve been distributed, creating a never-ending whack-a-mole situation for large game companies.

Are emulators safe?

Emulators themselves are completely safe to use, provided they are downloaded from reputable sources on the web. For mobile devices, the Google Play Store will root out any bad actors, but PC emulators will require more of a discerning eye.

The same is true for ROMs. Downloading ROMs for games you don’t own is illegal, and many of the websites hosting these ROMs are sketchy. We won’t link any websites here, but you’re better off relying on online communities rather than search engines in this regard. Also make sure your antivirus and anti-malware software is up-to-date before running any ROMs you don’t trust.

If you’re worried about emulators damaging your PC, don’t be. The worst that can happen is that the emulator crashes or you may need to restart your PC. In any case, reputable emulator developers will release updates to improve performance and stability or fix bugs, so you should regularly update them.