| ILCA | (Research) Institute for Languages and Cultures of Asia and Africa | In English | → Research institutes → Civilization, culture, progress → Language, linguistics, literature → Area studies |
| ILCSM | IEEE (Institute of Electrical and Electronics Engineers) LCS Magazine | In English | → Serial publications, periodicals → Telecommunications |
| ILEI | Internacia Ligo de Esperantistaj Instruistoj | In Esperanto | → Organizations and associations → Education |
| ILERA | Internacia Ligo de Esperantistaj Radioamatoroj | In Esperanto | → Organizations and associations → Telecommunications |
| ILIPT | Intelligent Logistics for Innovative Product Technologies | In English | → Maintenance and logistics |
| IllOB | Bulletin of the Astronomical Observatory of the University of Illinois | In English | → Serial publications, periodicals → Astronomy |
| ILM | Internationales Logistikmanagement | In German | → Maintenance and logistics |
| ILM | Information Lifecycle Management | In English | → Document processing → Knowledge management |
| ILM | Institut für Laboratoriumsmedizin, Klinische Chemie und Molekulare Diagnostik | In German | → Research institutes → Biochemistry, biophysics → Pharmacology, toxicology → 6160 |
| ILMF | Intermediate-Level Maintenance Facility | In English | → Maintenance and logistics |
| ILO | Integrated Logistics Operations | In English | → Maintenance and logistics |
| ILP | Integrated Logistics Panel | In English | → Maintenance and logistics |
| ILP | Inductive Logic Programming | In English | → Computer science → 5196 |
| ILR | International Labour Review | In English | → Serial publications, periodicals → Labour, labour economics |
| ILRF | International Labor Rights Fund | In English | → Organizations and associations → Labour, labour economics |
| ILS | Integrated Logistics Support | In English | → Maintenance and logistics |
| ILS | Integrated Logistics System | In English | → Maintenance and logistics |
| ILS | Integrated Library System = SIGB | Système Intégré de Gestion de Bibliothèque | In French = АБИС | Автоматизированные библиотечные информационные системы | In Russian |
In English | → Knowledge management → Libraries → Software |
| ILS | International Libertarian Solidarity = SIL | Solidarité Internationale Libertaire | In French |
In English | → Organizations and associations → Political parties and movements |
| ILSA | Integrated Logistics Support Analysis | In English | → Maintenance and logistics |
| ILSC | Integrated Logistics Support Concept | In English | → Maintenance and logistics |
| ILSCP | Integrated Logistics Support Concept Plan | In English | → Maintenance and logistics |
| ILSIM | Integration of Lethality Studies Into Model | In English | → Maintenance and logistics |
| ILSMT | Integrated Logistics Support Management Team | In English | → Maintenance and logistics |
| ILSP | Integrated Logistics Support Plan | In English | → Maintenance and logistics |
| ILSSM | Israeli Society for Sexual Medicine | In English | → Organizations and associations → Sexual problems → Urology → Applied sciences, technology |
| ILSWG | Integrated Logistics Support Working Group | In English | → Organizations and associations → Maintenance and logistics |
| ILTS | IEEE (Institute of Electrical and Electronics Engineers) LTS | In English | → Serial publications, periodicals → Telecommunications |
| IM | Interface Module | In English | → Human-computer interaction |
| IM | Information Memory | In English | → Memories |
| IM | Individua Membro | In Esperanto | → Organizations and associations |
| IMA | International Medical Association | In English | → Associations → Medicine |
| IMA | Interdisciplinary Medical Association | In English | → Associations → Medicine |
| IMA | Information, Medien, Agrar | In German | → Newspapers, journalism → Agricultural sciences |
| IMADR | International Movement Against All Forms of Discrimination and Racism | In English | → Organizations and associations → Feminism |
| IMADS | Information Management Assimilation and Delivery System | In English | → Maintenance and logistics |
| IMAP | Internet Message Access Protocol | In English | → Networks, communication → Telecommunications |
| IMAP4 | Internet Message Access Protocol | In English | → Networks, communication |
| IMAS | Institutional Management Accounting System | In English | → Management |
| IMBA | Illinois Mortgage Bankers Association | In English | → Associations → Finance |
| IMBA | Internationale Motorsport Bond voor Amateurs (www.imba-mx.com) | In Dutch | → Organizations and associations → Vehicle engineering → Transport and postal services |
| IMBA | International Mountain Bicycling Association (www.imba.com) | In English | → Associations → Sport, physical exercises |
| IMCB | Institute of Molecular and Cell Biology | In English | → Research institutes → Biological sciences |
| IMCO | Intergovernmental Maritime Consultative Organization | In English | → Organizations and associations → International relations → 6295 → Transport and postal services |
| IMCP | Integrated Monitor and Control Panel | In English | → Human-computer interaction |
| IMDB | Integrated Maintenance Data Base | In English | → Data → Maintenance and logistics |
| IMDb | Internet Movie Database | In English | → Libraries → Cinema, movies |
| IMeRv | International Metals Reviews | In English | → Serial publications, periodicals → Metallurgy |
| IMGWL | IEEE (Institute of Electrical and Electronics Engineers) Microwave and Guided Wave Letters | In English | → Serial publications, periodicals → Telecommunications |
| IMI | Irish Management Institute | In English | → Management |
| IMIC | Integrated Management Information Computer | In English | → Management |
| IMIC | Integrated Management Information Center | In English | → Management |
| IMIT | Institute for Management of Innovation and Technology | In English | → Management → Engineering, technology |
| IMIX | Interactieve Multimodale Informatie Extractie | In Dutch | → Computer science |
| IMM | Institut Marocain de Management | In French | → Management → Higher education, universities |
| IMN | Instytut Metali Nieżelaznych (www.imn.gliwice.pl) | In Polish | → Research institutes → Metallurgy |
| IMO | Integration Management Office | In English | → Management |
| IMOD | Informatique et Mathématiques de l'Organisation et de la Décision | In French | → Computer science → Management → Mathematics |
| IMP | Information Management Plan | In English | → Knowledge management |
| IMP | Initial Memory Protection | In English | → Memories |
| IMP | Inventory Management Plan | In English | → Management |
| IMP | Innovative Management Partner | In English | → Management |
| IMP/LMM | Ingénierie des Matériaux Polymères/ Laboratoire Matériaux Macromoléculaires | In French | → Research institutes → 620 → Plastic industry |
| IMQ | Istituto Italiano del Marchio di Qualità (www.imq.it) | In Italian | → Quality management |
| IMRv | International Materials Reviews | In English | → Serial publications, periodicals → 620 |
| IMS | National Museums of Scotland | In English | → Museums |
| IMS | Inventory Management System | In English | → Knowledge management |
| IMS | Information Management System | In English | → Knowledge management |
| IMS | IP Multimedia Subsystem | In English | → Telecommunications → Computer science |
| IMS | Institute for Molecular Science | In English | → Research institutes → Biochemistry, biophysics |
| IMSO | International Mobile Satellite Organization | In English | → Associations → Spaceflight engineering, astronautics → Telecommunications |
| IMVN | Image, Multimédia et Vie Numérique | In French | → Computer science → Cinema, movies |
| INA | Integrated Network Analyzer | In English | → Networks, communication |
| INA | Internacia Naturkuraca Asocio | In Esperanto | → Associations |
| INA | International Nanoplankton Association | In English | → Associations → Marine research, oceanography → Palaeontology → Zoology |
| INA | Istituto Nuova Africa | In Italian | → Organizations and associations |
| INAP | Intelligent Network Application Part | In English | → Networks, communication → Telecommunications |
| InASP | Indian Academy of Sciences Proceedings | In English | → Serial publications, periodicals → Mathematics and natural sciences |
| INCA | International Newspaper Colour Association | In English | → Associations → Newspapers, journalism → Graphic industries, printing, publishing |
| InCh | Inorganic Chemistry | In English | → Serial publications, periodicals → Inorganic chemistry |
| INCITS | International Committee for Information Technology Standards | In English | → Standardization → Computer science → Telecommunications |
| InCo | Information and Computation | In English | → Serial publications, periodicals → Computer science |
| INCOPA | Inorganic Coagulants Producers Association (www.incopa.org) | In English | → Associations → Chemicals |
| INDOC | Indonesisch Documentatie en Informatie Centrum | In Dutch | → Libraries → Area studies |
| INED | Institut National d'Études Démographiques | In French | → Research institutes → Demography |
| INEI | Institutul Naţional de Economie şi Informaţie | In Romanian | → Economics → Computer science |
| INEN | Instituto Ecuatoriano de Normalización | In Spanish | → Standardization |
| InEPS | Indian Academy of Sciences Proceedings: Earth and Planetary Sciences | In English | → Serial publications, periodicals → Astronomy → Earth sciences |
| INERIS | Institut National de l'Environnement Industriel et des Risques | In French | → Research institutes → Nature → Engineering, technology |
| InES | Indian Academy of Sciences Proceedings: Engineering Sciences | In English | → Serial publications, periodicals → Engineering, technology |
| INESASS | Institute of National Economy - Shanghai Academy of Social Sciences | In English | → Research institutes → Economics |
| İNETD | İnternet Teknolojileri Derneği | In Turkish | → Organizations and associations → Networks, communication |
| INETI | Instituto Nacional de Engenharia e Tecnologia Industrial | In Portuguese | → Research institutes → Engineering, technology |
| InfCo | Information Control | In English | → Serial publications, periodicals → Computer science |
| InfD | Information Display | In English | → Serial publications, periodicals → Computer science |
| InFer | Integrated Ferroelectrics | In English | → Serial publications, periodicals → Electrical engineering |
| InfPh | Infrared Physics | In English | → Serial publications, periodicals → Physics |
| INFRAWEBS | Intelligent Framework for Generating Open (Adaptable) Development Platforms for Web - Service Enabled Applications | In English | → Software → Internet → Telecommunications |
| IngAr | Ingenieur Archiv | In German | → Serial publications, periodicals → Engineering, technology |
| InGeo | International Geophysics Series | In English | → Serial publications, periodicals → Geophysics |
| INI | Institut National d'Informatique | In French | → Specialized or (poly)technical colleges → Computer science |
| InISA | Indian Institute of Science - Journal of Aeronomical Society of India | In English | → Serial publications, periodicals → Mathematics and natural sciences |
| InISJ | Indian Institute of Science Journal | In English | → Serial publications, periodicals → Mathematics and natural sciences |
| INIST | Institut National d'Information Scientifique et Technique | In French | → Libraries → Mathematics and natural sciences → Applied sciences, technology |
| InJAE | Indian Journal of Aerospace Engineering Division | In English | → Serial publications, periodicals → Aeronautics, aircraft → Spaceflight engineering, astronautics |
| InJBB | Indian Journal of Biochemistry and Biophysics | In English | → Serial publications, periodicals → Biochemistry, biophysics |
| INJENO | INitiatives de parents de Jeunes Épileptiques du Nord | In French | → Organizations and associations → Neurology |
| InJME | Indian Journal of Mechanical Engineering Division | In English | → Serial publications, periodicals → Mechanical engineering |
| InJP | Indian Journal of Physics and Proceedings of the Indian Assocatiation for the Cultivation of Science | In English | → Serial publications, periodicals → Mathematics and natural sciences → Physics |
| InJTP | Indian Journal of Theoretical Physics | In English | → Serial publications, periodicals → Physics |
| INM | Institutul Naţional de Metrologie | In Romanian | → Standardization |
| InMat | Inventiones Mathematicae | In Latin | → Serial publications, periodicals → Mathematics |
| InMP | Instytut Maszyn Przepływowych | In Polish | → Serial publications, periodicals |
| InMS | Indian Academy of Sciences Proceedings: Mathematical Sciences | In English | → Serial publications, periodicals → Mathematics |
| INN | Instituto Nacional de Normalización (www.inn.cl) | In Spanish | → Standardization |
| INNORPI | Institut National de la Normalisation et de la Propriété Industrielle | In French | → Standardization → Industrial property |
| INOE | Internacia Naturista Organizo Esperantista | In Esperanto | → Organizations and associations |
| INPADOCDB | International Patent Documentation Data Base | In English | → Libraries → Industrial property |
| InPhT | Infrared Physics and Technology | In English | → Serial publications, periodicals → Physics |
| INPMA | Institut National des Plantes Médicinales et Aromatiques | In English | → Research institutes → Biological sciences → Pharmacology, toxicology → Agricultural sciences |
| INRETS | Institut National de Recherche sur les Transports et leur Sécurité | In French | → Research institutes → Transport and postal services → Vehicle engineering |
| INRIA | Institut National de Recherche en Informatique et Automatique | In French | → Research institutes → Computer science → Electrical engineering |
| INRIA | Institut National de Recherche en Informatique et en Automatique | In French | → Research institutes → Computer science → Mechanical engineering |
| INRS | Institut National de Recherche et de Sécurité | In French | → Research institutes |
| INSAP | Indian National Science Academy Proceedings Supplement | In English | → Serial publications, periodicals → Mathematics and natural sciences |
| INSP | Institut des Nanosciences de Paris | In French | → Research institutes → Physics → Chemistry |
| INSTAC | Information Technology Research and Standardization Center | In English | → Computer science → Telecommunications |
| INSTM | Institut National des Sciences et des Techniques Nucléaires | In French | → Research institutes → Nuclear, atomic, and molecular physics → Nuclear technology |
| INTAP | Interoperability Technology Association for Information Processing | In English | → Associations → Telecommunications → Computer-based techniques |
| INTEC | Independent Terminal Testing and Certification Consortium | In English | → Quality management |
| INTEC | International Netcourse Teacher Enhancement Coalition | In English | → Organizations and associations → Education |
| INTECO | Instituto de Normas Técnicas de Costa Rica (www.inteco.or.cr) | In Spanish | → Standardization |
| InTEEC | Information Technology and Electrical Engineering Consult | In English | → Computer science → Electrical engineering |
| INTMK | Itogi Nauki i Tekhniki Seriia Meteorologiia i Klimatologiia | In Russian | → Serial publications, periodicals → Meteorology, climatology |
| INTOSAI | International Organization of Supreme Audit Institutions | In English | → Organizations and associations → Accounting → 659 |
| INTSA | Итоги науки и техники. Астрономия = INTSA | Itogi Nauki i Tekhniki. Seriia Astronomiia | In Russian |
In Russian | → Serial publications, periodicals → Astronomy |
| INTSA | Itogi Nauki i Tekhniki. Seriia Astronomiia = (look above) |
In Russian | → Serial publications, periodicals → Astronomy |
| INTSF | Itogi Nauki i Tekhniki Seriia Fizika Plazmy | In Russian | → Serial publications, periodicals → Plasma physics |
| INTSI | Itogi Nauki i Tekhniki Seriia Issledovanie Kosmicheskogo Prostranstva | In Russian | → Serial publications, periodicals → Astronomy |
| IntSM | Interavia Space Markets | In English | → Serial publications, periodicals → Aeronautics, aircraft → Spaceflight engineering, astronautics |
| INTSO | Itogi Nauki i Tekhniki Seriia Okeanologiia | In Russian | → Serial publications, periodicals → Marine research, oceanography |
| INTSR | Itogi Nauki i Tekhniki Seriia Radiotekhnika | In Russian | → Serial publications, periodicals → Telecommunications |
| INTSS | Itogi Nauki i Tekhniki Seriia Sovremennye Problemy Matematiki | In Russian | → Serial publications, periodicals → Mathematics |
| InvPr | Inverse Problems | In English | → Serial publications, periodicals → Mathematics |
| IO | Input/Output | In English | → Computer science → Engineering, technology |
| IOA | Input/Output Adapter | In English | → Data |
| IOAOB | Instituut voor de Organisatie van de Administraties der Openbare Besturen | In Dutch | → Research institutes → Libraries |
| IOB | Input/Output Buffer | In English | → Data |
| IOB | Input/Output Bus | In English | → Data |
| IOB | Input/Output Box | In English | → Hardware → Data |
| IOBPS | Input/Output Box and Peripheral Simulator | In English | → Hardware → Data |
| IOC | Input/Output Controller | In English | → Data |
| IOC | International Olympic Committee (www.olympic.org) = CIO | Comité International Olympique | In French = МОК | Международен олимпийски комитет | In Bulgarian = MOO | Međunarodni olimpijski odbor | In Bosnian = COI | Comitè Olímpic Internacional | In Catalan = MOV | Mezinárodní olympijský výbor | In Czech = IOK | Internationales Olympisches Komitee | In German = ΔΟΕ | Διεθνής Ολυμπιακή Επιτροπή | In Greek = IOK | Internacia Olimpika Komitato | In Esperanto = COI | Comité Olímpico Internacional | In Spanish = ROK | Rahvusvaheline Olümpiakomitee | In Estonian = KOK | Kansainvälinen olympiakomitea | In Finnish = COI | Comité Olímpico Internacional | In Galician = MOO | Međunarodni olimpijski odbor | In Croatian = NOB | Nemzetközi Olimpiai Bizottság | In Hungarian = TOK | Tarptautinis olimpinis komitetas | In Lithuanian = IOC | Internationaal Olympisch Comité | In Dutch = IOK | (Den) internasjonale olympiske komité | In Norwegian = MKOI | Międzynarodowy Komitet Olimpijski | In Polish = COI | Comité Olímpico Internacional | In Portuguese = МОК | Международный олимпийский комитет | In Russian = MOK | Međunarodni olimpijski komitet | In Serbo-Croatian = MOV | Medzinárodný olympijský výbor | In Slovak = MOK | Mednarodni olimpijski komite | In Slovenian = МОК | Међународни олимпијски комитет | In Serbian = IOK | Internationella Olympiska Kommitté | In Swedish = МОК | Міжнародний олімпійський комітет | In Ukrainian |
In English | → Organizations and associations → Sport, physical exercises |
| IOC | Internationaal Olympisch Comité (www.olympic.org) = CIO, МОК, MOO, COI, MOV, IOK, ΔΟΕ, ROK, KOK, NOB, TOK, MKOI, MOK (look above) |
In Dutch | → Organizations and associations → Sport, physical exercises |
| IOCP | ITS On-Board Computer Program | In English | → Software |
| IODT | Integrated Ontology Development Toolkit | In English | → Programming languages → Data → Linguistics |
| IOK | Internationella Olympiska Kommitté (www.olympic.org) = IOC, CIO, МОК, MOO, COI, MOV, ΔΟΕ, ROK, KOK, NOB, TOK, MKOI, MOK (look above) |
In Swedish | → Organizations and associations → Sport, physical exercises |
| IOK | Internationales Olympisches Komitee (www.olympic.org) = IOC, CIO, МОК, MOO, COI, MOV, ΔΟΕ, ROK, KOK, NOB, TOK, MKOI, MOK (look above) |
In German | → Organizations and associations → Sport, physical exercises |
| IOK | (Den) internasjonale olympiske komité (www.olympic.org) = IOC, CIO, МОК, MOO, COI, MOV, ΔΟΕ, ROK, KOK, NOB, TOK, MKOI, MOK (look above) |
In Norwegian | → Organizations and associations → Sport, physical exercises |
| IOK | Internacia Olimpika Komitato (www.olympic.org) = IOC, CIO, МОК, MOO, COI, MOV, ΔΟΕ, ROK, KOK, NOB, TOK, MKOI, MOK (look above) |
In Esperanto | → Organizations and associations → Sport, physical exercises |
| IOLM | International Organization of Legal Metrology | In English | → Organizations and associations → Standardization |
| IOLS | Infrastructures et Outils Logiciels pour la Simulation | In French | → Computer science |
| IOM | Input/Output Module | In English | → Data |
| IOM | International Organization for Migration | In English | → Organizations and associations → Migrations |
| IOM | Interoceanmetal Joint Organization | In English | → Organizations and associations → Marine research, oceanography → Mining |
| IOP | Input/Output Part | In English | → Data |
| IOP | Input/Output Processor | In English | → Hardware → Data |
| IOP | International Organisation of Palaeobotany | In English | → Organizations and associations → Paleobotany, palynology |
| IOPAN | Instytut Oceanologii Polskiej Akademii Nauk (www.iopan.gda.pl) | In Polish | → Research institutes → Marine research, oceanography |
| IOPT | Input/Output Parameter Table | In English | → Data |
| IOQE | Input/Output Queue Element | In English | → Data |
| IORA | (Annuario publicado pelo) Imperial Observatorio do Rio de Janeiro | In Portuguese | → Serial publications, periodicals → Astronomy |
| IORL | Input/Output Requirements Language | In English | → Data |
| IORP | Imperial Observatório do Rio de Janeiro | In Portuguese | → Serial publications, periodicals → Observatories |
| IORTD | Input/Output Relationships and Timing Diagram | In English | → Data |
| IOS | Input/Output Supervisor | In English | → Data |
| IOSCS | International Organization for Septuagint and Cognate Studies | In English | → Organizations and associations → Judaism → Christianity |
| IOT | Individuum Organisation Technologie | In German | → Computer science → 659 |
| IOT | Inspraakorgaan Turken (in Nederland) | In Dutch | → Organizations and associations → Migrations |
| IOU | Input/Output Unit | In English | → Data |
| IP | Instrument Processor | In English | → Hardware |
| IP | Interfacing Processor | In English | → Hardware → Human-computer interaction |
| IP | Internet Protocol | In English | → Internet |
| IPA | Fraunhofer-Institut für Produktionstechnik und Automatisierung | In German | → Research institutes → Engineering, technology |
| IPA | Information-technology Promotion Agency | In English | → Computer science → Telecommunications |
| IPA | Internet Privatstiftung Austria | In German | → Foundations → Networks, communication → Telecommunications |
| IPA | Internationales Phonetisches Alphabet = AFI | Alfabetul Fonetic Internaţional | In Romanian = LFE | Lizherenneg Fonetikel Etrebroadel | In Breton = МФА | Международната фонетична азбука | In Bulgarian = AFI | Alfabet fonètic internacional | In Catalan = IFA | Internacia Fonetika Alfabeto | In Esperanto = IPA | International Phonetic Alphabet | In English = ΔΦΑ | Διεθνές Φωνητικό Αλφάβητο | In Greek = IPA | Internationales Phonetisches Alphabet | In German = API | Alphabet Phonétique International | In French = AFI | Alfabeto Fonético Internacional | In Spanish = AFI | Alfabeto Fonético Internacional | In Galician = NAF | Nazioarteko Alfabeto Fonetikoa | In Basque = IPA | Internationalt Phonetescht Alphabet | In Letzeburgesh = AFI | Alfabeto Fonetico Internazionale | In Italian = МФА | Международный фонетический алфавит | In Russian = AFI | Alfabeto Fonético Internacional | In Portuguese = AFI | Alfabet fonetic internacionau | In Occitan = AFE | Alfabet Fonetike Eternåcionå | In Walloon = IFA | Internationoal Fonetisch Alfabet | VLS = AFN | Alfabeti Fonetik Ndërkombëtar | SQ |
[ALS] | → Writing systems |
| IPA | International Phonetic Alphabet = AFI, LFE, МФА, IFA, ΔΦΑ, API, NAF, AFE, AFN (look above) |
In English | → Writing systems |
| IPA | Internationales Phonetisches Alphabet = AFI, LFE, МФА, IFA, ΔΦΑ, API, NAF, AFE, AFN (look above) |
In German | → Writing systems |
| IPA | Interparlamentarische Arbeitsgemeinschaft | In German | → Associations → Parliaments, representation |
| IPA | Internationalt Phonetescht Alphabet = AFI, LFE, МФА, IFA, ΔΦΑ, API, NAF, AFE, AFN (look above) |
In Letzeburgesh | → Writing systems |
| IPA | International Publishers' Association | In English | → Associations → Graphic industries, printing, publishing |
| IPA | Independent Pilots Association | In English | → Associations → Aeronautics, aircraft |
| IPA | Independent Practice Association | In English | → Associations → Medicine |
| IPA | International Police Association | In English | → Associations → Police |
| IPA | International Psychoanalytical Association | In English | → Associations → Psychology |
| IPA | Institute for Programming research and Algorithmics | In English | → Computer science → Mathematics |
| IPA | International Phonetic Association | In English | → Associations → Writing systems |
| IPA | International Powerlifting Association | In English | → Associations |
| iPAC | Internet/Intranet Public Access Catalogue | In English | → Bibliography → Libraries → Networks, communication |