mputers to vanish by the early 1990s in the US. In Europe, the home computer remained a distinct presence for a few years more, with the low-end models of the 16-bit Amiga and Atari ST families being the dominant players, but by the mid-1990s even the European market had dwindled. – made by the same manufacturers, with compatible peripherals, operating systems, and application software.The Dutch government even ran a program that allowed businesses to sell computers tax-free to its employees, often accompanied by home training programs. Naturally, these businesses chose to equip their employees with the same systems they themselves were using. Today a computer bought for home use anywhere will be very similar to those used in offices
Many home computers were superficially similar. Most had a keyboard integrated into the same case as the motherboard, or, more frequently, a mainboard—while the expandable home computers appeared from the very start (the Apple II offered as much as seven expansion slots), as the whole segment was generally aimed downmarket, few offers were priced and/or positioned high enough to allow for such expandability. Some systems have only one expansion port, often realized in the form of cumbersome "sidecar" system, such as on the TI-99/4, or required finicky and unwieldy ribbon cables to connect the expansion modules.
Sometimes they were equipped with a cheap membrane or chiclet keyboard in the early days, although full-travel keyboards quickly became universal due to overwhelming consumer preference. Most systems could use an RF modulator to display 20–40 column text output on a home television. Indeed, the use of a television set as a display almost defines the pre-PC home computer. Although dedicated composite or "green screen" computer displays were available for this market segment and offered a sharper display, a monitor was often a later purchase made only after users had bought a floppy disk drive, printer, modem, and the other pieces of a full system. The reason for this was that while those TV-monitors had difficulty displaying the clear and readable 80-column text that became the industry standard at the time, the only consumers who really needed that were the power users utilizing the machine for business purposes, while the average casual consumer would use the system for games only and was content with the lower resolution for which a TV worked fine. An important exception was the Radio Shack TRS-80, the first mass-marketed computer for home use, which included its own 64-column display monitor and full-travel keyboard as standard features.
This "peripherals sold separately" approach is another defining characteristic of the home computer era. A first time computer buyer who brought a base C-64 system home and hooked it up to their TV would find they needed to buy a disk drive (the Commodore 1541 was the only fully compatible model) or Datasette before they could make use of it as anything but a game machine or TV Typewriter.
In the early part of the 1980s, the dominant microprocessors used in home computers were the 8-bit MOS Technology 6502 (Apple, Commodore, Atari, BBC Micro) and Zilog Z80 (TRS-80, ZX81, ZX Spectrum, Commodore 128, Amstrad CPC). One exception was the TI-99 series, announced in 1979 with a 16-bit TMS9900 CPU.The TI was originally to use the 8-bit 9985 processor designed especially for it, but this project was cancelled. However, the glue logic needed to retrofit the 16-bit CPU to an 8-bit 9985 system negated the advantages of the more powerful CPU. Another exception was the Soviet Elektronika BK series of 1984, which used the fully 16-bit and powerful for the time 1801 series CPU, offering a full PDP-11 compatibility and a fully functional Q-Bus slot, though at the cost of very anemic RAM and graphics. The Motorola 6809 was used by the Radio Shack TRS-80 Color Computer, the Fujitsu FM-7, and Dragon 32/64.
Processor clock rates were typically 1–2 MHz for 6502 and 6809 based CPU's and 2–4 MHz for Z80 based systems (yielding roughly equal performance), but this aspect 