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Here we take a ride once more—to witness the long, stormy history of the most popular OS today.

The History of the Operating System

The earliest computers were built for a particular purpose, and had their programming hard-wired into them. Data was given to the program through punch-cards, which could be altered easily. But to change the purpose of the machine, you needed to physically alter it, or buy a new one altogether.

Von Neumann to the Rescue

The Hungarian scientist John Louis von Neumann was the first to propose the idea of the “stored program”—where the code for the program was in the same memory area as the data. He figured (and correctly, too) that this wouldn’t be a problem, because the computer could tell the difference between data and code. Putting data and code together meant that computers could be more flexible, and reprogramming them wouldn’t be such a headache anymore.

Getting your work done

This is how you would write and run your program in the good old days:

This would become quite tedious, and soon it was proposed that some scheduling needed to be done. Programmers were given appointments in the day to come and run their programs. At the end of their appointment, they would give the machine to the next programmer. As the computers got more powerful, the time taken to finish a program grew lesser, and the computer would sit idle for longer. This was unacceptable—these were expensive machines, and people could not afford to let it just lie there, could they?

The first operating system

To ensure that the precious computers weren’t wasted, companies and educational institutions needed a system which ensured that programs are always running on it.

Believe it or not, the first operating system was human—fulltime computer operators who were hired to make sure that the computer would never be idle. Programmers would come to them with their programs on a punch-card and tell them to execute it. The operator would run the program, record the output, and give it to the programmer who would return after a nice snack.

The first real operating systems

Soon enough, programs were written that would perform the tasks of the computer operator—they would run a program, free up the resources used by it, and move on to run the next program. These were the first computer operating systems.

Every programmer used to write his or her own code to generate an output for their program, and the makers of the OS wanted to relieve them of this as well. This led to the introduction of the device driver—programs that could already talk to hardware. So programmers now just needed to write code to talk to the driver, rather than write their own drivers. It was also decided to give programmers a set of library functions—basic functionality that nearly all programmers would use. The management capabilities, device drivers and library functions together made up the structure of the OS—a structure it has even today.