This early HP mini-computer was a technological first, the first mini-computer relying on semiconductor memory (CMOS chips from then new startup Intel), instead of the magnetic core memory used in 1950-1960's computers. Logic is made of individual TTL circuit gates and some CuTL (the first integrated circuit series that was used in the Apollo Moon mission computer), carried over from the HP 2100 it replaced. And yes, it has blinkenlights on the front panel!
These interrupt-driven, I/O rich, DMA equipped, 16 bit computers were very good for real time, control and measurement applications. They have literally hundreds of I/O interface card options available, which makes them ideal to run a large range of interesting vintage peripherals, from 9 track mag tape to paper tape punches to card readers to TTYs to HP test instruments. The series 1000 was not obsoleted until 1989.