Development Index
DI-1 Primitive: people live in hunter-gatherer bands using stone tools.
DI-2 Pre-Industrial: people live in farming communities and cities. They use metal tools, but do not have mass production. Equivalent to Earth from 4000 BC to 1800 AD.
DI-3 Basic Industrial: population is more urbanized with mass production, railroads, telegraphy. Equivalent to Earth 19th century.
DI-4 Developed Industrial: massive urbanization, aircraft, automobiles, rocketry. Equivalent to Earth 20th century.
DI-5 Advanced Industrial: sophisticated computers, advanced, reusable rocketry, in-system space travel. Equivalent to Earth 21st century.
DI-6 Early Warp Space Drive 1, Anti-matter power. 22nd century equivalent.
DI-7 NEL Standard: Space Drive 2, 25th century, developed worlds of the NEL
DI-8 NEL Advanced: Space Drive 3, 25th century, best progress on Earth. Standard Development level of the PGU
DI-9 Ultra-Tech: Space Drive 4+, cutting edge of Earth secret research and some alien worlds
DI-10 Ancient Relic: super weird stuff, found in ancient ruins of immense antiquity from long before the PGU