Processors surround us everywhere - they are in computers, telephones, clocks, and even in refrigerators and teapots. However, they can easily be divided into two or three groups on common grounds (for example, ARM and x86), and in each group there were models that seriously advanced the processor industry forward - about them and talk.
Intel 4004 (1971).
The processor from which it all started - yes, of course there were processors before it, but it was the first commercial "stone", which in principle could be bought by everyone. Its characteristics were more than modest - the frequency was up to 740 KHz, it was 4-bit, and it cost about 200 dollars (for example - for such money you can now take a good quad-core Intel Core i5). However, its capabilities are quite enough for calculators to work - it was for them that it was developed.
Intel 8086 (1978).
It was with this processor that we began to use the x86 command set, which is now in all processors from Intel and AMD. So in theory, modern software after some adaptation can be run on this 10 MHz "pebble". It was also the first 16-bit processor from Intel, so in the end it could address as much as 1 MB of memory - a huge volume by those standards.
Zilog Z80 (1976).
Perhaps, one of the most famous processors thanks to the Sinclair ZX Spectrum - a personal computer that cost very cheaply, and therefore for 17 months it sold as much as one million copies. The processor itself was binary compatible with the popular Intel 8080, so with the launch of the programs there were no problems. Well, because of Speccy's huge popularity, huge amounts of programs and games were written for this processor, moreover - they are even written now (yes, under the 3-10 MHz processor of 30 years ago), so the processor can be called safely The longest-living among the processors for personal computers.
RCA 1802 (1976).
With the development of rocket technology, it quickly became clear that because of the high level of solar radiation (mostly), conventional silicon processors quickly degrade and cease to work, so for long space flights one must either make serious defense (which greatly increases the weight of the satellite), or Use another semiconductor or substrate. The first option, of course, was discarded - for the satellites of the 70s, each gram was counted, but the second option was a success - the RCA 1802 processor was built using silicon-on-sapphire (SPS) technology and possessing high stability both for statics and for radiation. And the processor did not fail - it was installed in the research probe Galileo, who studied Jupiter, and worked without problems for almost 15 years (from 1989 to 2003), while processing more than 30 gigabytes of information (and this at a frequency of only 1. 7 MHz).
MOS Technology 6502 (1975).
A processor that many people know by the Apple II computer in which it stood. But his popularity he got earlier because of the fact that at a price of only $ 25 he competed with Intel 8080 and Motorola 6800, which cost about $ 200. Of course, the competitors then lowered the price (more than twice - up to 70-80 dollars), but this only spurred sales of 6502. By the standards of the mid-70th this was a fairly powerful processor that could address up to 64 KB of memory. As a result, it was put into gaming consoles, where the price of components was important (by the way, in Dandy, it was NES, it was he), and in cheap PCs (thereby seriously spurring the home computer market).
Motorola 68000 (1980).
"The last exhalation of the great Motorola". The company, which at that time had already been involved with processors for a long time, began to take it-its main mistake was that it did not care for compatibility: if Intel has already released x86 processors for almost 5 years, Motorola has always done something new. So it happened with 68k - it was a powerful 32-bit processor with a frequency of up to 20 MHz, it was actively installed in personal computers from Amiga and Apple, it even traveled to space, being involved in Space Shuttle. But, alas, he did not really have any sequels, at the end of the 90th Motorola tried to go into embedded solutions, but even there cheaper ARM-processors did not allow it to develop any way.
PowerPC 601 (1992).
Power architecture was quite a serious competitor to x86, and all because it was seriously invested by Apple and IBM: they perfectly understood that Motorola can not alone make a new good processor, and Apple and IBM need to put something in their devices - so AIM was born (according to the first letters of the companies that included it), and in 1992 appeared the processor 601, operating at a frequency of 66 MHz. As a result, the architecture continued to evolve to the middle of zero, until it became clear that x86 is still better. The last device on the Power architecture can be considered Xbox 360, which is relatively relevant even now.
AMD Opteron 240 (2003).
It was the first x86 architecture processor to know how to physically perform 64-bit applications. Intel at that time had nothing to offer - yes, their Itanium knew how to execute 64-bit code, but with 32-bit code, which was then in 99% of the programs, they worked slower than Opteron. There were a lot of advantages in 64-bit addressing, the most basic one is the possibility of working with more than 4 GB of memory, and in Windows XP this has already been implemented.
Pentuim III (2000).
In the 90s, a tough race started for megahertz - every new generation had an increasingly smaller process technology and all the best layout of transistors, which eventually led to the fact that the 1 GHz band was conquered in Pentium III in 2000. Since then, the frequencies have grown very low, to 3-5 GHz, and the performance of steel has increased "in breadth" - multi-core processors began to appear.
Intel Pentium D (2005).
After losing the race for 64-bit processors, Intel decided to tighten up and create the first custom dual-core processor - and they succeeded: in 2005 they released dual-core Pentium, although by modern standards this is not exactly a dual-core processor - there are two processors under one lid, Elements. Such a scheme worked badly, and software that supports multithreading, then there was no. But still it gave impetus to the development of multi-core processors, where, by the way, Intel still loses - AMD now offers users eight-core solutions, when Intel - only quad-core (and soon - six-core).
After 2005 something globally new in the processors more, alas, did not appear - yes, now the processors have a L3 cache and even L4, but this is a logical development of L2. Processors have 4-8 cores - a logical development of multi-core. The frequencies on average were about 3 GHz in 2005, so they are now left. And even 128-bit processors did not appear in the near future, because up to the memory limit of x64 processors is still very, very far away. Moreover - we are getting closer to the limit on the size of a silicon transistor, and now we are actively developing new absolutely new processors. So who knows - maybe in 20 years, we will work on quantum PCs, and on modern Core i7 watch as we are now looking at some Pentium III.