A widely used metric of the level of development of a technology, with the highest level being ready for deployment.
Technology Readiness Levels
Level 1: Basic Research
Level 2: Applied Research
Level 3: Critical Concept or Proof of Function Established
Level 4: Lab Testing/Validation of Alpha Prototype Component/Process
Level 5: Laboratory Testing of Integrated/Semi-Integrated System
Level 6: Prototype System Verified
Level 7: Integrated Pilot System Demonstrated
Level 8: System Incorporated in Commercial Design
Level 9: System Proven and Ready for Full Commercial Deployment