Let's All Learn Some Cellphone Acronyms

Let’s face it. Cellphones are here to stay and you need to know a little something about how they work if you’re going to know which one is right for you. Over at Yahoo! they’ve got a list of some cell phone acronyms that you could learn, thereby increasing your knowledge of the world around you. We know most of our readers are pretty well versed in everything cellphone, but its still worth taking a look.

The most important ones to know?

GSM: “Short for Global System for Mobile Communications, GSM is the most widespread standard for cell phones networks in the world. If you’re a jetsetter who likes keeping in touch during your far-flung travels, you should go with a GSM-enabled phone, and here in the U.S., AT&T and T-Mobile are both GSM carriers. Besides the technical differences between CDMA and GSM networks (I’ll spare you the details), the main distinction of a GSM phone is that it comes with a SIM (Subscriber Identity Module) card.”

CDMA: “Short for Code Division Multiple Access, CDMA networks are much more prevalent in the U.S. than they are abroad, and while CDMA boasts many of the same features as GSM networks (including caller ID, call waiting, and text messaging), there are some key differences–namely, CDMA phones don’t use SIM cards. Instead, your phone’s identity and number are programmed into the handset by your carrier, and you can’t easily switch numbers on CDMA phones as you can with SIM-equipped GSM phones. Also, CDMA phones can only handle three-way conference calls, versus six-way calls on GSM networks. Major CDMA carriers in the U.S. include Sprint, Verizon Wireless, and regional operator Alltel.”

What this means for you: GSM phones can be “unlocked” and used with other carriers. Why is this important? If you have Cingular (AT&T) and want T-Mobile, you can keep your phone. Or, if you want to go to Europe, you can have your phone unlocked and buy a temporary SIM card from a European phone company.

With CDMA, you can’t. Simple as that. —MEGHANN MARCO

Basic Cell Phone Acronyms You Need to Know [Yahoo!]
(Photo: TheeErin)


Edit Your Comment

  1. cgmaetc says:

    Also, it’s sometimes far more economical to buy a phone from the manufacturer, then have your cell phone provider activate it. When you buy from the provider, you get locked into a contract with ever-changing plan addendum’s and ETFs.

  2. weave says:

    Unlocked phones direct from the manufacturer often have more features — like the latest Nokia high-end phones do wifi and because of that you can load a Voice over IP (internet phone calling) program on it. Carriers tend to strip features that might make them suffer “revenue leaks.”

    For example, with Gizmo on my Nokia I can sit in an internet cafe in Europe and call the U.S. for only 1.9 cents a minute. Normal GSM roaming rates are 99 cents for t-mobile.

    Unlocked phones cost more (unsubsidised) but you can do so much more with them.

  3. LatherRinseRepeat says:

    I bought an unlocked Motorola V3i. It came with all the accessories that are supposed to come with it. Every feature was enabled. No annoying Cingular start-up screens. No annoying Cingular logo on the external display. It even came with a full version of the Motorola Phone Tools software. And best of all, I didn’t have to extend my contract.

    I played around with my friend’s Verizon Motorola KRZR. It’s a real tragedy what Verizon does. Not only do they cripple some essential features, they also replace the Motorola user interface with their own crappy Verizon UI and menus. The phone is barely usable.

  4. Topcat says:

    I hate to be that grammar patsy, but GSM and CDMA aren’t acronyms- they’re abbreviations. Acronyms are abbreviations pronounced like words (such as UNICEF).

    Also, for the Canadian audience:
    Rogers and Fido: GSM
    Bell, Virgin, Solo, Telus: CDMA

  5. larry_y says:

    There’s also UMTS: “Universal Mobile Telecommunications System”, which is the technological successor to GSM. It offers high speed data (like CDMA systems); UMTS phones also support GSM when a UMTS network is unavailable.

    In the US, only at&t has deployed UMTS.

  6. vr4z06gt says:


    I think rogers either has or had a CDMA component whenever i used to roam in downeast maine at college on a verizon cell phone it would say i was on a rogers tower.

  7. John Stracke says:


    GSM and CDMA aren’t acronyms

    I’ve heard this argument before, and I say they’re acronyms, because that’s what everybody calls them. Making a distinction between acronyms which are pronounced as words, and those which are pronounced as letters, is just not useful.

    Some people call them “initialisms”, which I find to be a pretty clumsy term.


    There’s also UMTS

    Yes, that was covered in the article. They even mentioned the difference between UMTS and HSDPA.

    What wasn’t covered in the article is the problem of frequency. In the US (and, I think, in Canada), GSM phones use 850MHz and 1900MHz; in the rest of the world, they use 900MHz and 1800MHz. That’s why you need a tri-band, or, better yet, quad-band phone if you want to roam from the US to, say, Europe.

    The same problem is repeating with 3G. Cingular’s 3G network runs at 850MHz and 1900MHz, same as their ordinary GSM; the rest of the world is on 2100MHz. When T-Mobile launches their 3G, they’ll be using 1700MHz and 2100MHz, but not the same part of the 2100MHz band as the rest of the world. So, if you walk into CompUSA and buy a Nokia N80, which is supposed to be a 3G phone, you won’t be able to get 3G service in the US. Similarly, if you buy a 3G phone from Cingular or T-Mobile, you won’t be able to use its 3G features with anybody else’s network.

    Aren’t standards wonderful? There are so many to choose from!

  8. dbeahn says:

    Is it just me, or does it seem like call quality is just better on CDMA (also known as TDMA) networks? You also don’t get that “speaker pop” on CDMA like you do on GSM.

    I love how GSM is marketed as “3G” or “next generation”. The technology is actually older than CDMA, but because you can “use a simm card!” it’s marketed as a leap forward in the US. Change phones and keep your info! Sacrifice nothing except the quality of your voice calls!”

  9. legerdemain says:

    CDMA supports R-UIM cards, a feature found on many Nokia handsets sold in the US market. Sadly, no US carrier is actually using these cards, and the few phones with such a slot ship with the slot disabled in firmware.

    Also, I have read a significant number of anecdotal reports of people using Sprint and Alltel phones on Verizon, though there are issues. One problem is that the phones are only useful for voice calls, as each carrier uses very different settings for data and text. If you have a special phone, you probably want the special features. The other problem is that you’ll then be using Verizon.

  10. tschepsit says:

    What? A list of cellphone acronyms without “ETF”?

  11. plim says:

    Actually, an acronym can be an unpronounceable word made up of initials.

    try using MW to get your defs straight =)


    Main Entry: ac·ro·nym
    Pronunciation: ‘a-kr&-“nim
    Function: noun
    Etymology: acr- + -onym
    : a word (as NATO, radar, or laser) formed from the initial letter or letters of each of the successive parts or major parts of a compound term; also : an abbreviation (as FBI) formed from initial letters : INITIALISM

    besides, cdma and gsm aren’t abbreviations. their abbreviation would be something like cddivmulacc or gblsysmblcomm


    Main Entry: ab·bre·vi·a·tion
    Pronunciation: &-“brE-vE-‘A-sh&n
    Function: noun
    1 : the act or result of abbreviating : ABRIDGMENT
    2 : a shortened form of a written word or phrase used in place of the whole (amt is an abbreviation for amount)

    (had to replace the

  12. DjSnipSnip says:

    Great post, and to add to it: when switching SIMs between carriers; one should pay attention to carrier bandwidth: the frequency the operator transmits. For example: T-mobile operates on 1900MHz band and their phones are mostly 900/1800/1900 where as Cingular/AT&T operates on 850/1900 MHz. In short, using a T-mobile phone with AT&T service IN SOME markets might be possible but in low quality. More important use of phones from europe (operating on 900/1800 MHz) in the states or vice versa might be troublesome.

  13. racermd says:

    Is it just me, or does it seem like call quality is just better on CDMA (also known as TDMA) networks? You also don’t get that “speaker pop” on CDMA like you do on GSM”

    Actually, TDMA stands for Time Division Multiple Access and is very distinct from CDMA. TDMA slices up the frequency being used into (very small) time slices. CDMA uses a spread-spectrum method, but everyone can be on at the same time.

    While three of the four words are identical and both achieve the same goal of allowing multiple users to use the same frequencies at the same time, the methods used are quite different.

  14. saikofish says:

    Awesome post. I’m a big fan of tri-band or quad-band GSM phones because like Meghann said, they’re incredibly useful while travelling around the world. I get a local phone number wherever I go! So here’s some tips and resources if you want to try the same thing:

    More on the frequency differences and a handy chart of what country uses what frequencies at the Travel Insider: http://www.thetravelinsider.info/roadwarriorcontent/quadba… (unfortunately, list is about 2 years old now)

    More in-depth data at GSM World: http://www.gsmworld.com/roaming/gsminfo/index.shtml
    It’ll give you all the carriers in each country, a map of their coverage range, and what frequencies each carrier uses. Good to do this research in advance; you don’t want to buy a SIM card for a carrier that won’t use the frequencies on your phone!

    Lastly for all you Nokia phone users.. how to unlock your phone yourself! http://unlock.nokiafree.org/
    It’s a little bit technical but once you know what you’re doing it’s super easy to unlock Nokia phones which is why I tend to use only Nokias. Not really for the faint of heart, though, because if you mess up a couple of times it’ll disable the phone completely. Still, I’ve done it several times on my phones and my friend’s and family’s phones without incident.

  15. Tush says:

    The biggest reason I didn’t go with Verizon or Sprint was that they use CDMA. The closed nature of CDMA really bothers me, and I want to be able to take my phone internationally and use it.

    Ideally Verizon and Sprint should switch to GSM, but they won’t because they want more control over you.

  16. virgilstar says:

    Forget about voice signal… everyone now wants to use their cellphone for DATA!

    The major reason I went with Verizon is that I find CDMA to give a better data signal in “odd” places. GSM cell towers need to be closer together (higher frequency travels shorter distances), so the overall coverage of GSM networks is not as good as CDMA. CDMA signals are better at penetrating buildings… for example right now in a large hospital complex I have 3 bars on a verizon phone while my colleague on T-mobile has zero signal at all.

    I know T-Mobile and Cingular keep banging on about rolling-out their 3G coverage, but they’ve been saying this for years and years, and in the meantime their data subscribers have to put up with awful “EDGE” service. For those of us in the real world that need 3G right now, then CDMA’s EVDO data is really the only current workable solution. Sure in some limited markets you can get reliable GSM 3G service, but those places are few and far between.

    This becomes even more of a joke when you consider the types of things people do with data-enabled ‘phones, such as Google maps mobile. What use is a mapping application if you can’t get a signal as soon as you step outside the city limits? IMHO, EVDO is still king when it comes to data.

  17. mroach says:


    Actually these days T-Mobile’s tri-band phones are 850/1800/1900 because of all their newish roaming agreements with smaller regional providers.


    Nobody is calling GSM next generation, they’re calling UMTS and HSDPA next generation. GSM has been around since the late 80s. Maybe you saw 3GSM, which is sort of the transitional name for GSM to UMTS.

    I’m 3GSM/GSM for life. I love importing phones and being able to switch between phones at will. It’s also really nice to be able to use my phone in other countries without any hassle at all. I typically get a local pre-paid SIM too if I’m going to be there a while so I get more reasonable data, voice, and SMS rates. The closed and anti-consumer nature of CDMA and the providers that use it is pretty appalling and I’d never everbe a subscriber of theirs.

  18. asplodzor says:

    @ weave

    If you use Grandcentral and tie it to your Gizmo’s SIP number, you’ll be able to make free calls. :-) GC even has a WAP interface so you can do everything on board your phone.

    The more you know…

  19. audiogeek says:

    The annoying little pop, or that super awful mosquito type sound you get with GSM is actually a big problem in the audio world. The interference thrown off by GSM devices, and everyone has a blackberry, et al, that constantly pulls, will be heard in news broadcasts a lot coming up.

    I use a Samsung quad band device, with Sprint. GSM internationally and CDMA in North America. Works really well, although I do have to manually choose one data network for each country in Europe.

    When doing field recording in Italy recently I got the ugly buzzing in the recording when mobile device checked email, but turning it off alleviates the problem.

  20. sfreeman says:

    “CDMA signals are better at penetrating buildings…”

    The physics virgilstar uses to justify this statement is correct, but I’m not convinced that’s all that’s going on. The difference in signal reception may also be based on multipath problems that occur in single frequency tranceivers (like GSM). Because CDMA transmissions consist of many frequencies, data can still be recovered even when several frequencies are attenuated due to multipath effects (results in fewer ‘dead’ spots in and around buildings)

    Also, absent from this debate is the technical advantage of CDMA over GSM in regards to battery life. Even though CDMA power amps in the transmit path are less efficient than GSM power amps due to linearity requirements, CDMA has its power transmission levels constantly adjusted by the the base station through continuous monitoring. So, CDMA, in an urban setting (near base stations), uses considerably less power than GSM. (If you live in Kansas though, you should definately go with GSM).

    So while the other concerns listed here are certainly valid: no sim cards, limited features, etc, when it comes to choosing the better technology for city living, there is no contest.

  21. The Walking Eye says:

    @virgilstar: Forget about voice signal… everyone now wants to use their cellphone for DATA!

    I, for one, could care less about data on my cell phone. I’ve got a computer for that kind of stuff, and this thing called an atlas for my maps. I don’t really have a need for maps on my phone, or the internet, or photos, etc. Give me strong signals, good voice quality, and good call holding and I’m peachy.

  22. AaronT says:

    “Ideally Verizon and Sprint should switch to GSM, but they won’t because they want more control over you.”

    That’s one possible reason… Another is that switching from CDMA (specifically, IS-95 and CDMA2000) to GSM would require replacing billions of dollars-worth of equipment and millions of phone handsets. It would also mean a reduction in network capacity. GSM uses a form of TDMA, and as such, has a hard limit to the call capacity of each channel, unlike the more sophisticated CDMA. That’s why UMTS (GSM’s successor) uses a form of CDMA instead.