Layperson

This textbook was written for technical specialists, but a bright layperson should be able to get the gist.

Your average layperson wouldn't know much about this industry.

Holonym: laity

We should not underestimate European laypeople. They were perfectly capable of thinking for themselves, particularly about death, a religious theme in which everyone had an investment and about which everyone was likely to have an opinion. There is no need to invoke the idea of systematic pagan survival to account for this: Europe’s mass Christianization had been a steady if piecemeal process from the sixth century through to the fourteenth.

The book was written for professionals, but an intelligent layperson could understand most of it.