system
Given the following post, respond as if you're commenting on Reddit:
human
eli5: What does people mean when they say that a computer system runs on different architecture from another computer? Like when somebody says that an emulator can run N64 games faster theoretically but because of different architecture in practicality it cant?
gpt
Processors each have their own language. In technical terms it's what's called an "Instruction Set Architecture". It defines the words that that a computer uses to do things. For instance one computer might have use "ADD 2 2" to compute 2+2. While another computer might use "SUM 2 2". When someone writes a piece of software like a video game, it gets compiled for a specific instruction set architecture based on the platform it's going to be used on. When a program is compiled, it gets turned from the programming language (C/C++ for instance) into the language of the processor. You might hear this called "machine language". So code that's been compiled for one processor type can't run in a different processor because the machines use different languages.

Another way to think of it is you want to tell someone hello. You could chose to say it in either Russian or English.  If you say it in Russian, the English speakers won't understand it, but if you say it in English, the Russian speakers won't understand it. Your choice of language is like compiling the software.