From a cut-in-half City to a Ferrari-fighter
The NSX traces back to early-1980s Honda experiments - famously a Honda City test mule cut in half with the engine moved behind the driver. That fed into the 1984 Pininfarina-designed HP-X concept, which evolved into the NS-X prototype ("New Sports eXperimental"). The production car was led by Executive Chief Engineer Shigeru Uehara and Chief Designer Masahito Nakano. Honda's brief was explicit: match Italian and German supercars, but do it with Honda reliability and a lower price.
The VTEC V6 and the aluminum body
The original plan used a non-VTEC 3.0-liter DOHC V6. Late in development - reportedly at the urging of Honda president Tadashi Kume - the engine was re-engineered to use VTEC, gaining a stronger block and titanium connecting rods that pushed the redline to 8,000 rpm. The new C30A was physically larger, forcing engineers to tilt it back about 5 degrees to fit. The body was the other headline: an all-aluminum monocoque, a production first, paired with aluminum suspension arms and (later) the first electronic throttle in a Honda road car.
Senna's role - handled carefully
The popular story is that Ayrton Senna "developed" the NSX. The more careful, sourced version: Senna, then a Honda-powered McLaren F1 driver, tested a prototype at Suzuka and told Honda the chassis felt insufficiently rigid. Honda used that feedback (among other inputs) and ultimately stiffened the structure by over 50 percent. But Wikipedia, citing Japanese-language sources, explicitly cautions that Senna was not the development driver - he drove the car only a handful of times and offered advice. The actual lead development driver was Motoharu "Gan-san" Kurosawa, with much chassis work done at the Nürburgring, plus on-track input from Satoru Nakajima and Bobby Rahal. We present Senna's contribution as real but limited, and flag the "development driver" framing as a disputed/overstated claim.
Variants and the long run
Over 15 years the NSX spawned a broad family: the original Coupe; the targa-roofed NSX-T (1995-on); the JDM track-special NSX-R / Type R (NA1, ~1992-95); the JDM Type S and ultra-rare Type S-Zero (1997-2001); the US-only Alex Zanardi Edition (1999, 51 cars); and a second NSX-R (NA2) on the 2002 facelift car. The big mechanical watershed was 1997, when manual cars got the larger 3.2-liter C32B (the NA2) and a 6-speed gearbox; automatics kept the 3.0 (NA1) to the end. In December 2001 the car was facelifted - most visibly, the pop-up headlamps gave way to fixed xenon units - and it ran in that form until production ended 30 November 2005.