Okay, let's pretend you are building something with a big pile of different shaped Lego pieces. Each of these Lego pieces can do different things - some can make buildings, some can make cars, and some can make animals.
Now, a regular instruction set is like someone telling you to build a specific thing with these Legos, like a building or a car. But an orthogonal instruction set is like someone giving you instructions to build anything you want with these Legos, no matter what shapes or colors they are.
Instead of limiting you to building certain things, an orthogonal instruction set gives you the freedom to use any Lego piece you want to build whatever you can imagine. It's like having an instruction set that works with every piece in your Lego collection, instead of just certain ones.
So, an orthogonal instruction set is like someone giving you the power to build whatever you want, however you want, with the tools you have available. It's all about freedom and flexibility, and making it easy to create anything you can dream up!