It is the more surprising to discover to which extent the few standards in existence were taken as a basis to create an increasing variety of code tables in actual systems. Not only manufacturers took the opportunity to make their products different from those of their competitors, but even within a company like IBM incompatibilities were multiplying. Only in the last years uniformity appears to become a desirable target again.
Some classification is needed to get a clear picture of the present situation.
Variants of ISO 8859, that is C1 and G1 completed to the rules, are only few. The C0 and C1 space is used for graphic characters, and G1 has a content of its own. Some octets, however, may be interpreted as a control character, dependent on the software that is active at the moment. This is regretted now. Atari presented a completely individual filling, in which even Hebrew letters occur.