To ease the transition to Apple Silicon Macs, Apple allows developers to create a universal binary file, which is an application file that can run on both older Intel and modern Apple Silicon Macs. We explain what they are and how they work.
It is an application that runs on Intel and Apple Silicon Macs
In 2020, Apple introduced a new type of Mac powered by Apple Silicon (with the M1 and M2 chips), which represents a different type of computer architecture than previous Intel Macs. This means that Apple Silicon Macs cannot run programs written for Intel Macs without some help.
Apple created two solutions to bridge compatibility between older Intel-based Macs and newer Apple Silicon-based Macs, starting with the M1 chip. The first is Rosetta 2, which is a translation layer that allows Intel applications to run at near-native speed on Apple Silicon Macs. The second is Universal Binary. Universal Binaries are applications that have been compiled to work with Intel and ARM processors. This means that you can run the same application file on both an Apple Silicon Mac and an Intel Mac.
Note: Universal Binaries aren’t new to Apple Silicon Macs: Apple also used the same branding during its transition from PowerPC to Intel Macs in 2006. And the computer industry’s tradition of packing binaries for two architectures into a single file (called a “fat binary “) goes back much further than that.
Universal Binaries runs natively on Apple Silicon Macs with Apple’s M-series chips, which means they run faster and more efficiently than Intel-only applications that must run through Rosetta 2. If we use Apple’s previous architecture transition between PowerPC and Intel as a For example, during the first few years of the transition, many applications are likely to be universal. But as Apple Silicon adoption grows over time, developers are likely to shift to producing only native Apple Silicon apps.
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Advantages for developers
For software developers, Universal Binaries offers a great advantage: they can launch a single .APP file that can be used on both types of Macs. This means that there is no need to distribute two separate versions of the same software program.
Developers typically create universal binaries by compiling the source code of a software program twice, once for each type of processor. They then combine the resulting executable files into a single universal (or “Universal 2”) binary file.
While universal binaries offer great benefits, a small drawback is that universal binaries are typically larger in size than standard executable files. Still, during a period of architectural transition, Universal Binaries allows users to run software programs on any type of Mac without having to worry as much about compatibility.
Universal Binary Tips
Now that you know what a universal binary is, you might be wondering: am I using one right now? You can check if an app is a universal binary by right-clicking the app’s icon in Finder and choosing “Get Info” from the menu that appears. If the app is a universal binary, you’ll see “Application (universal)” in the “Type” field.
Also, in the “Get Info” window, you can choose whether to run the Intel version of the application on Rosetta instead of the native Apple Silicon version. To do so, check the “Open in Rosetta” box.
The next time you open the app, the Intel version of the app will run. If you want to run the native Apple Silicon app again later, right-click the app icon, choose “Get Info” and then uncheck “Open with Rosetta”. Have fun!
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