We’re going to take our first baby steps from hardware into software! Using that CPU we built last episode, The Central Processing Unit: Computer Science Crash Course #7, we’re going to run some instructions and walk you through how a program operates on the machine level. We'll show you how different programs can be used to perform different tasks, and how software can unlock new capabilities that aren't built into the hardware.
We’re going to look at how CPU speeds have rapidly increased from just a few cycles per second to gigahertz! Some of that improvement, of course, has come from faster and more efficient transistors, but a number of hardware designs have been implemented to boost performance.
So you may have heard of Moore's Law and while it isn't truly a law it has pretty closely estimated a trend we've seen in the advancement of computing technologies. Moore's Law states that we'll see approximately a 2x increase in transistors in the same space every two years, and while this may not be true for much longer, it has dictated the advancements we've seen since the introduction of transistors in the mid-1950s. So today we're going to talk about those improvements in hardware that made this possible - starting with the third generation of computing and integrated circuits (or ICs) and printed circuit boards (or PCBs). But as these technologies advanced a newer manufacturing process would bring us to the nanoscale manufacturing we have today - photolithography.
Computers keep getting faster and faster, and by the start of the 1950s, they had gotten so fast that it often took longer to manually load programs via punch cards than to actually run them! The solution was the operating system (or OS), which is just a program with special privileges that allows it to run and manage other programs. So today, we’re going to trace the development of operating systems from the Multics and Atlas Supervisor to Unix and MS-DOS, and take a look at how these systems heavily influenced popular OSes like Linux, Windows, MacOS, and Android that we use today.