BACI stands for Ben-Ari Concurrent Interpreter. The compiler and interpreter originally were procedures in a program written by M. Ben-Ari, based on the original Pascal compiler by Niklaus Wirth. The original version of the BACI compiler and interpreter was created from that source code and was hosted on a PRIME mainframe. After several modifications and additions, this version was ported to a PC version in Turbo Pascal, to Sun Pascal, and to C. Finally, the compiler and interpreter were split into two separate programs. Recently, a C-- compiler has been added to the BACI suite of programs to compile source programs written in a restricted dialect of C++ into PCODE object code executable by the interpreter. Compared with other concurrent languages, BACI offers a variety of synchronization techniques with a syntax that is usually familiar. Any experienced C or Pascal programmer could use BACI within hours.