K

K is a family of programming languages developed and licensed by Arthur Whitney. All members of K are members of the APL-like language. The official implementation of K is maintained by KX Systems as part of kdb (K4). However, there exist open source implementation of K3 (Kona) and K7 (oK). Unlike APL however, K uses an ASCII representation much like J.

K3 was a key influence in the concatenative language F.