| ARC | 1947 | Excluded from Sammet | Initial orders | United Kingdom | Assembler for Booth |
| Arc | 2000 | United States | Exprimental LISP dialect | ||
| Arche | 2000 | Concurrent OO Language | |||
| Arche | 1992 | Experimental and other | France | ||
| ARCHI | 1986 | Experimental and other | United States | Microarchitecture description language | |
| Arctic | 1984 | Specialised Languages | United States | Real-time functional language, used for music synthesis. |