HP

Hewlett-Packard, or just HP is a company in the USA making several electronic devices, including calculators.

Calculators
Below are some of HP’s calculator models produced over the years, in numeric rather than chronological order:


 * HP 9G - Graphing calculator designed by Kinpo Electronics, Inc.
 * HP-11C - Scientific Programmable, including hyperbolics, gamma function, statistical functions, and random number generation.
 * HP-12C – The financially centric calculator from the HP-10 series introduced in the 1980s. The longest running product in the HP calculator line, it remains in production.
 * HP-15C - Advanced Scientific Programmable, including hyperbolics, gamma function, combinatorial and statistical functions, random number generation, numerical integration, numerical root finding, plus comprehensive matrix operations and full support for complex numbers.
 * HP-16C - Computer science calculator that could perform binary arithmetic and boolean logic functions.
 * HP-17B - Financial calculator superseding the 12C, with two-line display, alphanumerics and sophisticated Solve functions rather than step programming. Uses the Saturn chip set.
 * HP-19C - 1977 calculator with RPN and built in thermal printer. Included a programming language with looping and branching.
 * HP-20S - A basic scientific calculator, using infix notation, barely programmable and with no graphing capabilities.
 * HP-25 - The Owner's Handbook is dated 1975. Programs could be written with up to 49 steps, its batteries were rechargeable with charger included. Reverse Polish notation (RPN) was used.
 * HP-28C (1987) RPN Scientific graphing calculator. First graphing calculator, and introduced the forth-like RPL (programming language), programmable keys, and symbolic equation solving, with 2k of user memory. Book-style design (flip-open cover) with keys on both interior halves. Intended for programs to be entered, used, and then deleted.
 * HP-28S (1988) Expansion of HP-28C; 32 kB of user memory due to customer base using the HP-28C in unintended ways (keeping programs in memory for long periods). Introduced a file system for storing variables, functions, and user programs. Like the HP-28C, this model used the "open-book" physical design. Functionally a direct predecessor to the HP-48 series, which returned to a more traditional physical design based on the HP-41.
 * HP-29C - 1977 calculator with RPN. Included a programming language with looping and branching. A value model of the 19C printer
 * HP 30s - Calculator designed by Kinpo Electronics, Inc.
 * HP-32S - Scientific programmable
 * HP 33s - Calculator designed by Kinpo Electronics, Inc.
 * HP-33C - Scientific Programmable - successor to the HP25 and HP25C.
 * HP-34C - First Calculator with Integration and Root Finding
 * HP-35 -- The original
 * HP 35s -- Introduced to commemorate the 35th anniversary of the HP-35, it is an advanced scientific programmable calculator, featuring algebraic and RPN modes, hyperbolics, statistics, numerical integration, numerical solver, random number generation, equations, and full programmability using up to 32 Kb of RAM for programs and data.
 * HP-38G -- a simplified successor to the HP-48, using infix notation.
 * HP-39g series - A successor to the HP-38, using infix notation.
 * HP-40 series. A successor to the HP-38, using infix notation.
 * HP-41 series – Three models in this series were released over its lifetime, the 41C, 41CV, and 41CX. The 41C had user configurable program steps and memory registers, alpha-numeric display, user programmable key mappings, and 4 expansion ports that could hold additional memory, an interface to HP-IL peripherals, a magnetic card reader/writer, or commercial application programs. The 41CV quadrupled the amount of base memory, and the 41CX added a clock and some additional functions and memory.
 * HP-42S – a non-expandable follow-up to the HP-41 series. It included a two line display (dot addressable) and featured built-in matrix and complex number mathematics.
 * HP-45 - a follow up to the HP-35 with 10 memories, extra functions and display format selection.
 * HP-48 series. Scientific, programmable graphing calculator. Based on the functionality of the HP-28 series, but with a return to a traditional appearance (similar to the HP-41 series). Historically one of the most popular models among engineers; programmable and with graphics. Introduced a filesystem in the form of a multi-level tree (similar to Unix filesystems) and a real-time clock, and an operating system which could turn on the calculator, and sound an alarm, or run a program.
 * HP-49 series. Enhanced versions of the 48 series. Later models designed by Kinpo Electronics, Inc.
 * HP-50g - As of 2007, the latest member of the HP-49 series.
 * HP-65 - First programmable pocket calculator
 * HP-67 and HP-97 - follow-up to HP-65, HP-97 is a desktop version.
 * HP-71B - Handheld model natively programmable in an extended BASIC language including a RAM-based filesystem, recursion, multiline user-defined functions and subprogram calling with parameter passing, but also capable of accepting plug-in ROM modules to provide such functionalities as full I/O capabilities to any type of device (printers, mass storage, measurement instruments), programmability in other languages (Forth, Assembler), advanced math capabilities (such as matrix operations, support for complex numbers, multidimensional numerical integration and root finding, Fast Fourier Transforms, etc), as well as an advanced Calculator Mode capable of executing algebraic expressions one step at a time and undoing individual steps.