| EPL | ⊕ 1966 | ↓ ↑ ⊕ Multi-purpose | IBM PL/Is | ⊕ United States | Early PL/1 |
| MPL | ⊕ 1969 | ↓ ↑ ⊕ Multi-purpose | IBM PL/Is | ⊕ United States | Early name for PL/I |
| MPPL | ⊕ 1964 | ↓ ↑ ⊕ Multi-purpose | IBM PL/Is | ⊕ United States | Interim name for PL/I |
| NPL | ⊕ 1963 | ↓ ↑ ⊕ Experimental and other | IBM PL/Is | ⊕ United States | New Programming Language |
| PL/I | ⊕ 1964 | ↓ ↑ ⊕ Multi-purpose | IBM PL/Is | ⊕ United States | Programming Language One |
| PL/I Checkout Compiler | ⊕ 1972 | ↓ ↑ ⊕ Multi-purpose | IBM PL/Is | ⊕ United Kingdom | |
| 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 |