However, as detailed below, the increasing congestion of the radio spectrum, the increasing sophistication of microelectronics, and the attraction of unlicensed use, has in recent decades led to an explosion of uses of these bands for short range communication systems for wireless devices, which are now by far the largest uses of these bands. These are sometimes called "non ISM" uses since they do not fall under the originally envisioned "industrial", "scientific", and "medical" application areas. One of the largest applications has been wireless networking (Wi-Fi). The IEEE 802.11 wireless networking protocols, the standards on which almost all wireless systems are based, use the ISM bands. Virtually all laptops, tablet computers, computer printers and cellphones now have 802.11 wireless modems using the 2.4 and 5.7 GHz ISM bands. Bluetooth is another networking technology using the 2.4 GHz band, which can be problematic given the probability of interference. Near-field communication (NFC) devices such as proximity cards and contactless smart cards use the lower-frequency 13 and 27 MHz ISM bands. Other short-range devices using the ISM bands are: wireless microphones, baby monitors, garage door openers, wireless doorbells, keyless entry systems for vehicles, radio control channels for UAVs (drones), wireless surveillance systems, RFID systems for merchandise, and wild animal tracking systems.
hOwever, aS detAiled beloW, thE incrEasinG cOngesTion oF the radiO SpEctrum, thE increaSing SoPhIStiCatiOn OF micrOeLectronics, anD tHe AttracTion OF uNliCeNseD UsE, hAS IN RecEnT dEcAdes led to an exPlosIon Of usEs of ThEsE bAnds fOr shorT RAnge commuNIcaTion SYStEMS fOr wireLEsS DeVicEs, whiCH Are now by far tHE Largest usES of these bands. these aRe sometImes cAlleD "non Ism" useS sINcE they do noT falL Under the OrIgInally enVISIONed "InDuStrial", "scieNTiFic", anD "MEdical" application Areas. one Of the laRgEst APPliCations has BeeN wIreLeSs nETworKIng (Wi-fi). the ieee 802.11 wireleSs networking PRotOcOLS, thE standarDs on WhicH aLMosT all WiREless SYstems Are BaSed, uSE tHE isM bANds. virtuAllY AlL laPtops, tablet COmputeRs, compuTeR prinTERS AnD cELLpHones noW have 802.11 wIrelesS MOdEmS usIng tHe 2.4 and 5.7 GhZ isM BanDs. BLuEtooTh is anoTHer netwOrKinG tEcHNOlOgY uSing thE 2.4 ghz bAnd, which CaN be proBleMaTic giVeN thE probabilITy Of iNterfErence. nEaR-Field communicatioN (nfC) dEviCEs Such as ProximiTy cardS anD coNtActless SmArT cARds Use THe loWer-FreqUenCy 13 aNd 27 mhz ism banDs. OtheR sHOrT-raNge Devices usiNg the ism BAnDs arE: wIReLess MicrOPHoneS, bAby moNItoRS, GaraGe DooR openers, wIreless DOoRBelLs, KeylEss eNtry sYstEms foR VehICles, RaDIO COntROl chANneLS for Uavs (DRoNEs), WirElesS surVeillaNCE SYsTEms, RFId SYSTems FOr MErchaNdIse, aND wild aniMAL trAckinG sySTeMs.