APL2

APL2 was a significant re-implementation of APL by IBM which was developed from 1971 and first released in 1984. It provides many additions to the language, of which the most notable is nested (non-rectangular) array support. As of 2018 it is available for mainframe computers running z/OS or z/VM and workstations running AIX, Linux, Sun Solaris, and Microsoft Windows.

APL2's extensions to ISO 8485:1989 were standardised as ISO-IEC-13751. No further core language features have been added, but it feature a number of powerful Quad names.

The entire APL2 Products and Services Team was awarded the Iverson Award in 2007.