# What did “f” and “g” stand for on old HP calculators? **URL:** \ **Category:** Factual Questions\ **Created:** [January 1, 2023, 6:44am UTC](https://boards.straightdope.com/t/what-did-f-and-g-stand-for-on-old-hp-calculators/977452 "2023-01-01T06:44:41Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [January 2, 2023, 12:12pm UTC](https://boards.straightdope.com/t/what-did-f-and-g-stand-for-on-old-hp-calculators/977452/21 "2023-01-02T12:12:02Z")
> [@nightshadea](#): > > wow, im old enough grandpa had an old adding machine that looked like a small cash register and printed everything out like one and then dad had one of the first digital calculators that looked like a checkbook and the numbers looked like a speak and spell … and cost about 75.00 then by the late 80s you could get big solar calcs at k-mart for like 10 bucks (my fingers were too big for the ones the schools used for math class so mo bought me one …) My dad was so proud of how much money he saved, when he bought a $300 four-function electronic calculator, because a mechanical device would have cost $500. It did get some practical use, though. My mom was a second-grade teacher, and if her students were very good, they got to check their answers on the calculator, which really impressed them. ---
**Author:** ![Robot\_Arm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/robot_arm/32/18280_2.png) [@Robot\_Arm](https://boards.straightdope.com/u/Robot_Arm)\ **Post date:** [January 2, 2023, 7:22pm UTC](https://boards.straightdope.com/t/what-did-f-and-g-stand-for-on-old-hp-calculators/977452/22 "2023-01-02T19:22:53Z")
> [@CurtC](#): > > My first HP calculator was the 41C, which just had a yellow function key without a letter. And my 41C, which I bought in 1981, still works. > [@DPRK](#): > > Yet an HP-15C still cost $135. I was just using my 15C last night. If it ever gives up the ghost, I’ll definitely want to replace it. The weird thing is, I bought it in the '90s, and I can’t ever remember replacing the batteries. > [@DPRK](#): > > Made me remember that while lots of computer keyboards did, and still do, have a bunch of modifier keys, the old Symbolics keyboard had spelled-out names for all of them: TOP, GREEK/FRONT, SHIFT, HYPER, SUPER, META, and CTRL. (OK, “CTRL” is abbreviated. Why?? I have at least one laptop keyboard where the “Fn” and “Alt” keys are small enough so that the abbreviations are understandable, but the nice and big control key also says “Ctrl”, and the shift key has nothing but an up-arrow on it—especially confusing since there are regular arrow keys— and if they are trying to evoke a vintage typewriter or something, well, a Remington 12 distinctly says “SHIFT KEY”) Ah, yes, the Space Cadet Keyboard. [http://catb.org/jargon/html/S/space-cadet-keyboard.html](http://catb.org/jargon/html/S/space-cadet-keyboard.html) ---
**Author:** ![Nars\_Glinley](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/nars_glinley/32/8177_2.png) [@Nars\_Glinley](https://boards.straightdope.com/u/Nars_Glinley)\ **Post date:** [January 3, 2023, 1:34am UTC](https://boards.straightdope.com/t/what-did-f-and-g-stand-for-on-old-hp-calculators/977452/23 "2023-01-03T01:34:55Z")
> [@Robot\_Arm](#): > > I was just using my 15C last night. If it ever gives up the ghost, I’ll definitely want to replace it. > > The weird thing is, I bought it in the '90s, and I can’t ever remember replacing the batteries. I have a 15C app on my iPhone. ---
**Author:** ![Robot\_Arm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/robot_arm/32/18280_2.png) [@Robot\_Arm](https://boards.straightdope.com/u/Robot_Arm)\ **Post date:** [January 3, 2023, 2:49am UTC](https://boards.straightdope.com/t/what-did-f-and-g-stand-for-on-old-hp-calculators/977452/24 "2023-01-03T02:49:48Z")
> [@Nars\_Glinley](#): > > I have a 15C app on my iPhone. I know that’s available, but I prefer the tactile feedback of the real thing, Plus, I often look things up my phone while I’m doing math, and it’s easier to have a phone and calculator than to switch between two apps. ---
**Author:** ![Francis\_Vaughan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/francis_vaughan/32/3093_2.png) [@Francis\_Vaughan](https://boards.straightdope.com/u/Francis_Vaughan)\ **Post date:** [January 3, 2023, 3:00am UTC](https://boards.straightdope.com/t/what-did-f-and-g-stand-for-on-old-hp-calculators/977452/25 "2023-01-03T03:00:23Z")
I have the HP-25 app on my phone. Sadly my real HP-25 won’t charge anymore, and since it uses ni-cad batteries, things are a bit hard. I use the app simply because, after all these years, my fingers know exactly where to go. And as implemented on the iPhone, it has a haptic click when you push the buttons 🙂 Still not quite the same as the real thing. I have a few other HP calculators, but once you go past the basics, going to a more powerful computational environment is much faster. There are a huge number to choose from. So for a calculator, HP-25 it is. ---
**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\ **Post date:** [January 3, 2023, 5:39am UTC](https://boards.straightdope.com/t/what-did-f-and-g-stand-for-on-old-hp-calculators/977452/26 "2023-01-03T05:39:43Z")
> [@Robot\_Arm](#): > > > [@Nars\_Glinley](#): > > > > I have a 15C app on my iPhone. > > I know that’s available, but I prefer the tactile feedback of the real thing, Plus, I often look things up my phone while I’m doing math, and it’s easier to have a phone and calculator than to switch between two apps. [I know you know all this] As far as I know, the HP-15C has not been produced since 2011 (that was a “limited edition” version brought back by popular demand, so, who knows, could always happen again) and used ones sell for multiples of their original price. However, the ROM image is available, so there are various emulators available— including virtual calculators published by HP [?] on their web site and for your phone, as well [various](https://www.swissmicros.com/product/dm15l) [clones](https://paxer.net/voyager/). The nice thing about those “Voyager” calculators is, they are reasonably small. Smaller and lighter than an iPhone 12, and the original consumed only 0.25 mW… ---
**Author:** ![Robot\_Arm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/robot_arm/32/18280_2.png) [@Robot\_Arm](https://boards.straightdope.com/u/Robot_Arm)\ **Post date:** [January 3, 2023, 5:58am UTC](https://boards.straightdope.com/t/what-did-f-and-g-stand-for-on-old-hp-calculators/977452/27 "2023-01-03T05:58:34Z")
> [@DPRK](#): > > However, the ROM image is available, so there are various emulators available— including virtual calculators published by HP [?] on their web site and for your phone, as well [various](https://www.swissmicros.com/product/dm15l) [clones](https://paxer.net/voyager/). The nice thing about those “Voyager” calculators is, they are reasonably small. Smaller and lighter than an iPhone 12, and the original consumed only 0.25 mW… Better than nothing, but I hope my original will keep going for a few more decades. Now that I think about it, I don’t remember what batteries it takes; are they still made? I’ve got an old 35mm camera with a light meter that clips on the top, and I couldn’t find the right battery for it. A smaller one with the same voltage seems to work. ---
**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\ **Post date:** [January 3, 2023, 6:07am UTC](https://boards.straightdope.com/t/what-did-f-and-g-stand-for-on-old-hp-calculators/977452/28 "2023-01-03T06:07:51Z")
LR1154 button cells? (e.g., Panasonic LR44 or Duracell MS76— the owner’s manual lists a bunch of recommended brands) ---
**Author:** ![nightshadea](https://avatars.discourse-cdn.com/v4/letter/n/7ba0ec/32.png) [@nightshadea](https://boards.straightdope.com/u/nightshadea)\ **Post date:** [January 3, 2023, 11:05am UTC](https://boards.straightdope.com/t/what-did-f-and-g-stand-for-on-old-hp-calculators/977452/29 "2023-01-03T11:05:32Z")
those you can get ---
**Author:** ![Robot\_Arm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/robot_arm/32/18280_2.png) [@Robot\_Arm](https://boards.straightdope.com/u/Robot_Arm)\ **Post date:** [January 3, 2023, 1:44pm UTC](https://boards.straightdope.com/t/what-did-f-and-g-stand-for-on-old-hp-calculators/977452/30 "2023-01-03T13:44:26Z")
I just checked my owner’s manual and it says A76 (alkaline) or 357 (silver-oxide). Those are both still available. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [January 3, 2023, 11:32pm UTC](https://boards.straightdope.com/t/what-did-f-and-g-stand-for-on-old-hp-calculators/977452/31 "2023-01-03T23:32:34Z")
Wow, bunch of old fogeys, here… I’m from the HP48 era, and that’s what I emulate on my phone. Although, my backup calculator is a slide rule, so… ---
**Author:** ![DavidNRockies](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/davidnrockies/32/6279_2.png) [@DavidNRockies](https://boards.straightdope.com/u/DavidNRockies)\ **Post date:** [January 3, 2023, 11:55pm UTC](https://boards.straightdope.com/t/what-did-f-and-g-stand-for-on-old-hp-calculators/977452/32 "2023-01-03T23:55:27Z")
It needed to be done (~ 5:00): [![](https://i.ytimg.com/vi/eSBybJGZoCU/hqdefault.jpg "Kraftwerk - Pocket Calculator") ](https://www.youtube.com/watch?v=eSBybJGZoCU) ---
**Author:** ![JohnGalt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johngalt/32/184_2.png) [@JohnGalt](https://boards.straightdope.com/u/JohnGalt)\ **Post date:** [January 5, 2023, 4:25am UTC](https://boards.straightdope.com/t/what-did-f-and-g-stand-for-on-old-hp-calculators/977452/33 "2023-01-05T04:25:41Z")
> [@Francis\_Vaughan](#): > > Sadly my real HP-25 won’t charge anymore, and since it uses ni-cad batteries, things are a bit hard. I have a collection of early calculators, many of which used ni-cad batteries. I’ve had decent luck going to a local battery store (such as BatteriesPlus+) and talk to the technicians there. They’ve always been kind of excited to rebuild a battery pack, which they said is a nice change of pace for them instead of just selling plain, standard AA and car batteries. ---
**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\ **Post date:** [January 18, 2023, 12:05am UTC](https://boards.straightdope.com/t/what-did-f-and-g-stand-for-on-old-hp-calculators/977452/34 "2023-01-18T00:05:53Z")
So I noticed a Logitech keyboard with “F” keys: F1, F2, F3, etc. But it also has “G” keys: G1, G2, …, G6. Not to mention “M” keys (memory?): [![](https://d3fa68hw0m2vcc.cloudfront.net/50c/78706421.jpeg) ](https://d3fa68hw0m2vcc.cloudfront.net/50c/78706421.jpeg) ---
**Author:** ![gnoitall](https://avatars.discourse-cdn.com/v4/letter/g/bb73d2/32.png) [@gnoitall](https://boards.straightdope.com/u/gnoitall)\ **Post date:** [January 18, 2023, 12:28am UTC](https://boards.straightdope.com/t/what-did-f-and-g-stand-for-on-old-hp-calculators/977452/35 "2023-01-18T00:28:02Z")
> [@DPRK](#): > > “M” keys (memory?): Macro key-set selector. The “G” keys can be loaded with stored keystroke sequences. The M\ buttons select among three different set of “G” key defintions. ---
**Author:** ![Omar\_Little](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/omar_little/32/269_2.png) [@Omar\_Little](https://boards.straightdope.com/u/Omar_Little)\ **Post date:** [February 1, 2023, 5:26pm UTC](https://boards.straightdope.com/t/what-did-f-and-g-stand-for-on-old-hp-calculators/977452/36 "2023-02-01T17:26:59Z")
The HP12c is still the best financial calculator out there. I got my first one over 30 years ago and still use one regularly. HP hasn’t really changed its functionality at all over that time and it still is a best seller. [![](https://m.media-amazon.com/images/I/81OsNAJACVL.jpg) ](https://m.media-amazon.com/images/I/81OsNAJACVL.jpg) Like most electronics, it’s more than half the cost today than a new one cost 30 years ago. ---
**Author:** ![Dogginit](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dogginit/32/16920_2.png) [@Dogginit](https://boards.straightdope.com/u/Dogginit)\ **Post date:** [February 1, 2023, 9:51pm UTC](https://boards.straightdope.com/t/what-did-f-and-g-stand-for-on-old-hp-calculators/977452/37 "2023-02-01T21:51:41Z")
> [@CurtC](#): > > My first HP calculator was the 41C, which just had a yellow function key without a letter. And my 41C, which I bought in 1981, still works. My 41CX that I’ve had for over 30 years died today 😭 ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [February 1, 2023, 10:04pm UTC](https://boards.straightdope.com/t/what-did-f-and-g-stand-for-on-old-hp-calculators/977452/38 "2023-02-01T22:04:55Z")
> [@Omar\_Little](#): > > HP hasn’t really changed its functionality at all over that time and it still is a best seller. Wait, I thought that HP had gotten entirely out of the calculator business a decade or more ago, and wasn’t making any any more. ---
**Author:** ![JohnGalt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johngalt/32/184_2.png) [@JohnGalt](https://boards.straightdope.com/u/JohnGalt)\ **Post date:** [February 1, 2023, 10:15pm UTC](https://boards.straightdope.com/t/what-did-f-and-g-stand-for-on-old-hp-calculators/977452/39 "2023-02-01T22:15:29Z")
So sad! During college I spent hours programming my HP-41C in 1980 (the original version). I actually had an interview upon graduation with HP in Corvallis where they looked closely at my notebook with about a dozen programs. I wish I knew where it went. I’ve collected about a dozen programmable calculators from that era; they all had a slightly different programming style, but HP had the best setup with the 41. ---
**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\ **Post date:** [February 2, 2023, 12:36am UTC](https://boards.straightdope.com/t/what-did-f-and-g-stand-for-on-old-hp-calculators/977452/40 "2023-02-02T00:36:26Z")
> [@Chronos](#): > > > [@Omar\_Little](#): > > > > HP hasn’t really changed its functionality at all over that time and it still is a best seller. > > Wait, I thought that HP had gotten entirely out of the calculator business a decade or more ago, and wasn’t making any any more. I don’t know the difference between HP, HP Inc., etc., but if you go to the official web site and click through a couple of times you get redirected to “official licensees” (Royal Consumer Information Products and/or Moravia Consulting) which are selling the calculators. (As well as “collaborating in the production, distribution, marketing, and support of HP branded calculators” and development of new HP calculator products.) [Previous page](https://boards.straightdope.com/t/what-did-f-and-g-stand-for-on-old-hp-calculators/977452.md?page=1)