Did you click on it? It's the document that describes what makes a wav file a wav file so that programs that can read wav files can read it. It's essentially a description and some instructions for the programmers making the reading program and the writing program so they know they're making the same file that contains the same information.

True, but the thing that makes lasers lasers and not just tiny flashlights is that they are a single coherent beam of uniform light. This is what allows them to behave reliably for engineering purposes and stay together over long distances, etc.

If I were to build a yellow laser by having a green laser and a red laser, it would be hard to get them to converge on exactly the same point. Or put another way, getting them to converge at a particular distance would be easy, but as soon as you moved slightly closer or further the dots would probably misalign and you'd end up with a red and green dot near each other. Even if the two beams were mirrored into the same trajectory, it's possible they'd refract while traveling due to their different wavelengths and end up as two dots at the end anyway.

I think it depends on what they meant by task switching. I think they meant "do a bit of game, then do a bit of web browser, then read some files, then back to game".

The GPU is good at doing the same "task", but a billion times, often with a huge amount of parallelism. So it's obviously good at switching from doing that task on one thing to doing that task on the next thing, but in the end it's still the same task.