| Abbreviation | Definition |
|---|---|
| PI | Path Identifier |
| PI | Presence Information |
| PI | Protocol Interpreter |
| PICS | Platform For Internet Content Selection |
| PIF | Peripheral Interface File |
| PIG | Port Ingestion Group |
| PIL | Platform Independence Layer |
| PIM | Protocol Independent Multicast |
| PIN | Plant Information Network |
| PINE | Program For Internet News And Email |
| PINS | Primary Interactive Network Sites |
| PINX | Private Integrated Services Network Exchange |
| PIO | Parrallel Input And Output |
| PIP | Postel's Internet Protocol |
| PIP | Programmable Interconnection Point |
| PIP | Projects In Progress |
| PISE | PowerShell Integrated Scripting Environment |
| PKCS | Public Key Cryptography Standard |
| PKI | Public Key Infrastructure |
| PKP | Public Key Partners |