The CPC's operating system was called [[AmsDOS]] (Amstrad's Disk Operating System) and was included on a ROM chip of 48KB. Also in ROM there was the Locomotive BASIC interpreter which made the CPC very fast in BASIC operations, compared to other contemporary machines.
== The 472 ==
[[image:CPC_472_es.jpg|right|thumb|200px|[[help:contents|Spanish Amstrad CPC 472]]]]
The CPC 472 was a spanish version of the CPC 464 with additional 8 KB RAM.
The reason Amstrad released a special version for the spanish market was a law that said that every computer with up to 64kb should adhere to some rules - namely, have extra keys for the spanish language otherwise an extra tax would be levied. So Amstrad soldered in an extra 8kb which was not, however, usable by the machine since it was not connected to anything else. Later on Amstrad released a 472 with a proper spanish keyboard and the 8 extra kB as well.
After the rule changed there was also a CPC 472 with non-spanish keys available for a very short time. The CPC 472 with spanish or british keyboard is very very rare.
== The 664 ==