| MPPL | ⊕ 1964 | ↓ ↑ ⊕ Multi-purpose | ⊕ IBM PL/Is | ⊕ United States | Interim name for PL/I |
| PL/I | ⊕ 1964 | ↓ ↑ ⊕ Multi-purpose | ⊕ IBM PL/Is | ⊕ United States | Programming Language One |
| PL/I Subset G | ⊕ 1964 | ↓ ↑ ⊕ Multi-purpose | ⊕ IBM PL/Is | ⊕ United States | General Purpose PL/I subset |
| PLITRAN | ⊕ 1964 | ↓ ↑ ⊕ Specialised Languages | ⊕ IBM PL/Is | ⊕ Australia | PL/I Preprocessor |