as far as english being the easiest to learn and most versatile, I'd have to put in that the technology for computers could never have come from certain language groups. We'd never have seen the concept develop from China or Japan because there simply wouldn't be any room to build a usable keyboard. There are just too many characters in those written languages. They might have developed machines that did certain calculations, but they'd never create anything as versatile as our current computer technology. Most asian languages are in the same boat. the current, English developed computer have had to be adapted to those languages, but they don't really work all that well.
Granted, it could have come from most countries in Europe (considering they have almost the same alphabet) but English speakers came up with the technology that has become the most widespread.
This has made English the most common language in the computer world, and by extension the business world. Trading and profit are the biggest motivators for doing anything. English has now become the most common language for doing business, even between countries where neither are native English speakers. Most of the business done between China and India is done speaking nothing but English.
It's really not a matter of which is easiest or best. (The same goes for computer technology in general.) It's what the most people have chosen to adopt for a very extensive list of reasons. Xerox was the first company to come up with a graphical user interface, and Mac may have even had the best in the beginning or even now, and Linux might even have the most flexible and adaptable, but it was Windows that became the most widely used. That's all there is to it.