In computer science, "IO" or "I/O" is commonly used as an abbreviation for input/output, which makes the .

However, it has become a generic domain and is popular in the tech world since IO or I/O means input/output in computer science. Each of them serves a specific purpose.

You can play the game offline, but there are several things you need to do first: Install MW3 via disc or download. If you're using a disc, you'll be prompted to download a 70+GB patch. If you purchased a digital download, skip to the next step.