At a high level, it is vaguely reminiscent of COBOL, as it has a 'Data Division' and a 'Procedure Division'; the syntax is closer to FORTRAN, but with block structure (with 'BEGIN' and 'END' statements). It has 'internal' and 'external' subroutines (the former without arguments, the latter with), and support for file operations.
The original version was for the PDP-8 family; there was sufficient interest that in 1971 a team produced a better compiler and interpreter. A time-sharing operating system allowed several users to run DIBOL applications simultaneously (in the same way that early versions of RSTS provided time-sharing for BASIC users on machines without hardware support for time-sharing).
In the mid-70's a version was produced for the PDP-11; DIBOL was eventually made available under RSTS/E, and later under RSX-11M-PLUS. It was also made available on the VAX; DIBOL-32 runs on VAX/VMS systems, although it can also be used on other systems through emulators.