Smart Common Input Method

The Smart Common Input Method (SCIM) is a platform for inputting more than thirty languages on computers, including Chinese-Japanese-Korean style character languages (CJK), and many European languages. It is used for POSIX-style operating systems including Linux and BSD. Its purposes are to provide a simple and powerful common interface for users from any country, and to provide a clear architecture for programming, so as to reduce time required to develop individual input methods.

Source: Wikipedia — Smart Common Input Method (CC BY-SA 4.0)