6. The Spice Series (1978 - 1983)
	HP 31E Introduced on May 1, 1978, this was the least expensive and simplest scientific model. With one yellow SHIFT key, it could provide basic scientific functions, some metric/imperial conversions and no programming capability.  It was a replacement of the HP 21. It was not very successful and, therefore, considerably rare. Code name: Ginger. Original price: $60
	HP 33E A new version of scientific calculator, introduced on May 1, 1978. It was almost an exact replacement of the HP 25, but this one could use subroutines. This series of calculators was the first that had a built in self-test operation, which could be accessed by pressing STO and ENTER. Code name: Sage. Original price: $100
	HP 38E Introduced on May 1, 1978. This was the first business model of the 3-series. Identical in functionality to the HP 38C, which was introduced on the same day. Code name: Chive. Original price: $120
	HP 32E This was a non-programmable model, but with statistical functions, more conversions and 15 data registers. Hyperbolic functions were finally added to HP calculators - even though HP felt that they were not needed - only because the Texas Instruments calculators of the time had them. Introduced on July 1, 1978. Code name: Thyme. Original price: $80
	HP 33C This was simply a 33E with continuous memory. Introduced on July 1, 1979. Code name: Sage C. Original price: $65
	HP 34C This was an advanced programmable model introduced on July 1, 1979, the same date as the 33C. Included numerical Solve and Integrate functions, as well as a Gamma function. The multiple functions required three shift keys, f, g and h. Code name: Basil. Original price: $150
	HP 37E Introduced on July 1, 1979, it was a new simpler business model without continuous memory and not programmable. A cheaper alternative to the HP 38E and 38C. A continuous memory version was never introduced. Code name: Parsley. Original price: $75
	HP 38C Introduced on May 1, 1978. This was the high-end business model of the 3-series. The "C" denoted that the calculator would preserve memory and any program steps after having been turned off. Identical in functionality to the HP 38E. Code name: Chive C. Original price: $150

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