| AIS | Automatic Identification Systems |
| ARPA | Automatic Radar Plotting Aid |
| BHP | Broken Hill Proprietary (Billiton) |
| CA | Cruising Association |
| dB | Decibels |
| DSC | Digital Selective Calling |
| DTI | Department of Trade and Industry |
| FTC | Fast Time Constant |
| GPS | Global Positioning System |
| IMO | International Maritime Organisation |
| ISPS | International Ship and Port Facility Security Code |
| KHz | Kilohertz (radio frequencies) |
| MCA | Maritime and Coastguard Agency |
| MDHB | Mersey Docks and Harbour Board |
| MRSC | Maritime Rescue Sub-Centre |
| MHz | Megahertz (radio frequencies) |
| MV | Motor Vessel |
| NFFO | National Federation of Fishermens Organisations |
| nm | Nautical mile (1852 metres) |
| OREI | Offshore Renewable Energy Installation |
| P & O | Peninsular and Orient ( Shipping Company) |
| RACON | Radar Beacon |
| RAF | Royal Air Force |
| RCS | Radar Cross Section |
| RIB | Rigid Inflatable Boat |
| RNLI | Royal National Lifeboat Institution |
| RPM | Revolutions Per Minute |
| RYA | Royal Yachting Association |
| SAR | Search and Rescue |
| SOLAS | Safety of Life at Sea |
| THLS | Trinity House Lighthouse Service |
| UHF | Ultra High Frequency |
| UK | United Kingdom |
| US | United States |
| μs | Microseconds |
| VHF | Very High Frequency |
| VTS | Vessel Traffic Services |
| WTG | Wind Turbine Generator |
