From this time onwards, as the title suggests, we have decided to deliver a series of articles that look back on the history of Mac OS and CPU transitions. Whether you're a recent Mac user or a long-time Mac user, it's hard to accurately recall the nearly 40-year history of the first Mac in 1984. Among them, events that may be helpful in exploring the direction of future Mac development are packed. Whether you are a long-time Mac user or a recent Mac user, I hope you will enjoy reading this book while feeling nostalgic about the past.
In this first installment, after confirming the major historical trends from the birth of the Mac to the present day, we will first take a quick look at the evolution of the CPU. The Mac has a long history as one of the active product series, but it will surprise you again that it has survived so many major CPU changes.
CPU and OS switch independently
Since its birth in 1984, the Mac is in the midst of several major changes. This major change was triggered by the plan to gradually transition all Mac CPUs to Apple Silicon, as announced at WWDC in 2020. Already at the end of last year, three models with Apple Silicon as the CPU were released at the same time. They are positioned as entry-class models among the Apple Silicon-equipped machines that will continue to appear. Despite this, it has demonstrated performance that surpasses even the middle range models so far, and it is still fresh in my memory that it has impressed us with the arrival of a new era of Macs with a different performance level than before.
Looking at the Mac OS, it was macOS Big Sur that was announced along with Apple Silicon at last year's WWDC. This version, of course, has a big mission to support Apple Silicon in addition to the previous Intel CPUs. The basic OS architecture doesn't look too different from the previous version (Catalina). There is no doubt that it inherits the major trend of the past and inherits the architecture of the OS based on Unix. It was originally called Mac OS X, then OS X, and then macOS.
The OS that has been installed on the Mac can be roughly divided into two types: the Classic system from the very beginning to before Mac OS X, and the Mac OS X system. Of course, there are many versions within each series, and it might be a little rough to lump them all together. Still, considering the architecture of the core part of the OS, it is certain that the systems before and after Mac OS X are completely different.
On the other hand, no matter how broadly the CPUs are divided, they will never be less than 4 types. There are four types: the MC68000 series adopted by the first Macintosh, the PowerPC series that migrated from it, the Intel series that was later replaced, and the Apple Silicon series this time.
Those who only know recent Macs may think that Macs use the same Intel CPU as Windows PCs from the beginning. However, even if you look at the Mac at the time when Mac OS X first appeared, it used a PowerPC instead of an Intel CPU. That is why it moved to Intel from the middle of the Mac OS X era. Looking back even further, the PowerPC did not appear at the same time as Mac OS X. It was first introduced long before that, in the Classic era, around System 7.1. Looking at it in this way, it can be seen that the Mac CPU and OS have undergone bold changes in their architecture at independent timings.
