The development of CP/M is pretty fun:

In 1972 Gary Kildall was working as a professor at the Naval Postgraduate School in Monterey, California, when he received funds to create a new computer lab. He soon used a contact at Intel to get a series of Intellec development model microcomputers for the lab by successfully pitching them on creating a new high level programming language for their CPUs.

Working as a consultant, Kildall created the "Programming Language for Microcomputers" - PL/M - based on an ancestor of IBM's PL/I language for their mainframes. (The I in PL/I is actually the Roman numeral "one"). Initially Intel's chips weren't powerful enough to self host a real language, so he ended up writing PL/M on a PDP/10 using an emulator, then compiling programs which he'd transfer to the microcomputers via paper tape.

Within a year or so, Intel had upgraded his computer to an Intellec 8/80 based on the 8080 CPU, which was finally capable of compiling and running PL/M programs on the machine itself. The problem was the 8/80's RAM was extremely limited and he didn't have any useful storage system in which to keep the code as he was writing it.

So Kildall talked a local floppy drive startup into giving him one of their older test drives for his lab. But Gary was a software guy! After several failed attempts at creating a controller board for the drive, it sat on a shelf for a year and he kept using the PDP/10 to write and compile programs for the new CPU. He finally asked for help getting the controller to work from a friend of his in Seattle, who came down to lend his hardware expertise. After a few months, they finally got the drive and the computer working together.

In 1974, after adding basic drive commands to PL/M, Gary used the language to create a simple disk "operating system" so he could load and run programs straight from disk. And thus, "Control Program Monitor" - CP/M - was born.

He originally offered it to Intel since they already licensed PL/M, but they turned it down. One thing lead to another and in 1975 he put an ad in a magazine offering the OS for use with the new wave of Altair style microcomputers being sold to the public and it took off.

The rest is well known history. Within five years, CP/M was the main operating system used for microcomputers, and in 10 it was an also-ran to DOS.

It goes to show how having early access to new technology has always been an important part of the industry, and how "fast followers" can often come along and upset the innovator so they become a footnote to history.