Since the lunar module would fly only in space (earth orbit and lunar vicinity), the designers could ignore the aerodynamic streamlining demanded by earth’s atmosphere and build the first true manned spacecraft, designed solely for operating in the spatial vacuum.
Lunar module generations from 1962 to 1969
James Webb examines models of the LEM and CM
Underside of LEM descent stage shows fuel tank installation
LEM Descent Stage
Mockup of LEM cabin with seats
1964 Version of LEM, No Seats and Triangular windows