Below is a simple version of games console history. The console titles that are in bold were the best selling consoles of their generation.

I only included the best-selling consoles, otherwise, the chart would have been too large. A console had to have sold at least a million units to be included on the chart. I actually used a handy list from wikipedia.

We can see the Sega/Nintendo war during the '80s and early '90s. It practically only involved 4 consoles (excluding add-ons like the Sega CD) which were the NES and Master System, and later the SNES and Mega Drive. During this time there was also a console called the TurboGrafx-16 which I've never heard of, but it sold over a million copies hence its inclusion in the chart.

Before constructing this chart I had only a dim idea of what consoles came before the Sega/Nintendo war. It turns out the main console was the Atari 2600. Why '2600'? Presumably, there was another Atari console before this one, which failed to sell 1 million copies and hence is not on the chart. Then they added an arbitrary large rounded number to its successor, a la the Xbox 360. Competing with the Atari were the Colecovision and Intellivision. Look how similar the names were. Who copied who? Well although it's not on the chart, the Intellivision came out first in 1980, so I suppose we can say that Coleco copied the idea of the putting 'vision' at the end of the console name for the Colecovision in 1982.