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The CP/M Operating System was first written in 1974 by Gary Kildall, who was half Norwegian. Well, his father was of Norwegian heritage, and his mom was part Swedish.
The operating system was based on ideas Gary Kildall had from Digital Equipment Corporation, DEC System 10, or PDP 10 that Gary used for the development of the CP/M.
Digital Equipment Corporation was founded in 1057 by Kenneth Harry "Ken" Olsen and co-founder Harlan Anderson. Ken's grandparents on his fathers side was both from Norway,
and his grandparents on his mothers side was both from Sweden. If Gary had a connection with Digital because of the Norwegian heritage of both himself and Ken I don't know.
Digital was a major computer company here in the US until it was bought by Compaq in 1998, another large American computer company, which merged with Hewlett Packard later.

At some point Intel made the 4004 processor, and later the 8008, which in it's turn was developed into the 8080. And this 8080 processor came in 1974. Some years later, in 1974
a new company was started, Zilog, and in 1976 their first microprocessor came out, the Zilog Z80. The Zilog Z80 was a better and more inexpensive processor than the Intel 8080,
Since both the 8080 and the Z80 could use the same software, CP/M became very a very popular operating system for the Z80 too.

The Amstrad PCW 8256 and PCW 8512 both use the Z80 processor, and run the CP/M operating system.

Part of the history is that in 1981, when IBM came out with the IBM PC, they needed an operating system, and went to Gary Kildall to talk to him. There are many stories about this,
and Microsoft and Bill Gates has made fun of Gary Kildall for not getting the deal. But it seems that IBM wanted the CP/M operating system ported to the 8086/8088 processor,
and the name changed to something of their own. Gary Kildall did not want that. IBM went to Bill Gates after that, and he had no operating system. But, he knew about someone who
had copied the CP/M without permission and made some changes to it and ported it to the Intel 8086/8088 processors. Bill Gates bought it, and presented it as their own system to
IBM and IBM called it PC-DOS, and Bill Gates and Microsoft sold it to others as MS-DOS.

This upset Gary Kildall, but the law in the US was not as clear as it is today for these things so Gary's lawyers adviced not to sue IBM or Microsoft. But, he got a deal with IBM
that said IBM was supposed to offer both operating systems on their PC. It was just that IBM sold PC-DOS for $40 and CP/M for $120. So no one wanted to pay $80 more just to get the
CP/M operating system. And Microsoft and Bill Gates have later mocked Gary Kildall and his company Digital Research and said they were not very smart people.
It happens to be so that Gary Kildall had a PhD in Computer Science, and made the operating system that in turn made Bill Gates rich, by buying stolen goods for $25,000.
After Digital Research was sold, there was a settlement between Microsoft and the new owners of CP/M, but small money compared to what Digital Research really lost.

Amstrad Computers was founded in 1968 by Alan Sugar. At some point Amstrad had a 60% market share in England, which is a lot.
Amstrad built quite a few different computers, but they were overshadowed by the IBM PC clones when the price dropped. However, Amstrad's idea about an inexpensive computer to get
the people going was not a bad idea in my opinion. And, the funny thing is that even those old computers they made in the mid 1985ties, they still work and are capable of doing
the same things they did 20-25 years ago. How many people use even 10% of the functions of a modern computer or 10% of Microsoft Word ? Sadly, Amstrad does not make computers for the consumer market anymore.

Picture will come soon