However, after many years of CPU generations, people noticed two groups started to appear: RISC and CISC processors.
Erm, no, nobody 'noticed two groups'. RISC computers were deliberately designed and designated that way. It wasn't some naming of an emergent phenomenon but a specific attempt to design computers around the idea that a Reduced (or simplified) Instruction Set would prove more efficient. The two pioneers were the RISC project at Berkeley run by David Patterson (SPARC and SOAR were direct descendents of this) and the MIPS project at Stanford run by John L. Hennessy, which is obviously the progenitor of the commercial MIPS architecture.
The respective heads of the two competing projects have since written books on computer architecture together which goes to show that competition and cooperation are not necessarily mutually exclusive.
Design and Implementation of RISC I. Séquin and Patterson (paper)
Unfortunate wording. There are ofcourse more ways to build a computer, like a single instruction machine, but in general RISC and CISC were "competing" architecture foundations.
There were genuine benefits to x86 and perhaps CISC at first. For example the variable sized instruction size saved memory, which is not as scarce as it was back in the day.
Actually, Intel has gone 1 step further and placed a bet on VLIW processors with the Itanium series. They abandoned them a few years ago.
Hummm. So what explains that we just bought a bunch of systems with IA64 CPUs?
They introduced the "last series" in march 2017, with no upcoming generation planned. They may sell these chips for the upcoming years to support these business and enterprise solutions. But without any upgrade path, you could very well speak of "abandoned".
Mostly now yeah. But:
- Apple and other manufacturers (with support from Microsoft) are looking into adopting ARM platforms for their laptops. Some of the newer "Smartphone" chips should reportedly compete with Intel Celeron's and Pentium's, which is plenty for a lot of people
Windows that doesn't run existing Windows apps pretty much eliminates the only reason to use Windows as opposed to Linux. In a world where Linux has more apps than Windows does, almost nobody would use Windows. And that's the situation with ARM.
Quantity is only a number that doesn't say much. It's always about the specific applications.
For example, if you do PCB design for a living then odds are high you're still on Windows. If you need more advanced tools than Eagle or KiCad can offer, and you can't afford Cadence stuff, then you're basically out of luck on the Linux platform (unless you want to hassle with VM's, Wine, or whatever).
Similarly a lot of people only need a webbrowser, email, calendar, office suite and perhaps be able to play the odd game. Some of these even can run in the browser; look at ChromeBooks.
MS tried Windows RT a few years back, and I think it flopped because who wants to deal with double versions and licensing for e.g. Office or other programs. If an ecosystem really becomes seamless across x86 and ARM I think you'll see more people stepping over.