| img | Psion OPL Image |
| imgsao | Aleph One Image |
| iml | IntelliJ IDEA Module |
| imp | FileMaker Pro Import Data Filter |
| Pascal/Delphi Implementation Data |
| in | GNU Autoconf Input File |
| in7 | Ox Data |
| ina | Alpha Five Form Definition Data |
| inc | ASP Include File |
| General Include File |
| Java Servlet Include |
| incr | Visual C# Compiler Incremental Data |
| index | Eclipse IDE Help Index |
| inh | Visual Basic Basfwin Data |
| inl | Visual C++ Inline Function File |
| inn | Micro Focus COBOL Overlay File |
| ino | Arduino Sketch |
| inspxe | Intel Inspector Results Data |
| int | Delphi Interface Unit |
| Micro Focus COBOL Intermediate Code |
| Visual FoxPro Codepage Data |
| into | Interspector Object |
| inventor | SGI Open Inventor Data |
| io | Modula-3 Compiled Object |
| iobj | Visual Studio Intermediate Object |
| iot | Hitachi Ladder Editor IO Comment |
| ipb | Apple iOS Perl Script |
| ipch | Intellisense Precompiled Header |
| ipdb | Visual Studio Internal Compilation Database |
| ipdl | IPC Protocol Definition Language Document |
| ipnb | IPython Notebook Document |
| ipp | Inline Guard Macro File |
| ipy | IPython Script |
| ipyn | IPython Notebook Document |
| ipynb | IPython Notebook Document |
| ipynd | IPython Notebook Document |
| ipynp | IPython Plot Document |
| ir | Crestron SIMPL IR Driver |
| irb | Interactive Ruby Script |
| ird | Crestron SIMPL IR Resource Data |
| ire | Ire Language Source Code |
| irev | LiveCode RevServer Script |
| irl | IBM WebSphere ILOG JRules Data |
| irobo | RoboMind Source Code |
| is | Modula-3 Intermediate Assembly File |
| is1 | Synergy/DE Data Index |
| isd | InstallShield Dialog |
| isl | InstallShield Pro Log |
| ism | Synergy/DE Data Index |
| isn | InstallShield Skin |
| iss | InstallShield Response File |
| itb | U-Boot uImage Image Tree Blob |
| itcl | Cygwin iwidgets Script |
| itf | JPI TopSpeed Pascal Interface File |
| itq | SAIA S-Web ITQ File |
| itrace | Microsoft Visual Studio iTrace Data |
| its | U-Boot uImage Image Tree Source |
| ivu | ImmerVision XML User Interface |
| ivy2 | Apache Ivy 2 Cache |
| iwb | IWBasic Source Code |
| iwdgt | iWeb Widget |
| iws | IntelliJ IDEA Workspace |
| ix3 | Instant.Exe 3.0 Script |
| ixx | Modula-3 Linker Information Data |
| izd | Intrexx Application Export Format Data |
| izs | 1st Page 2000 Script |
| i_caf | Amazon Lumberyard Intermediate CAF Data |
| j | Java Source Code |
| Java Source Code Dependency Data |
| j1 | EDIT Compiler JEDEC Boundary Data |
| j3o | JMonkey Engine 3D Object |
| jacl | IBM WebSphere Server ACL Script |
| Java Application Control Language Script |
| jadd | JastAdd Imperative Aspect |
| jade | Jade Markup Language Document |
| jak | AHEAD Tool Suite JAK File |
| jal | JAL Source Code |
| jam | Jam STAPL Source Code |
| jardesc | Eclipse JAR Description |
| jasper | JasperReports Compiled JRXML File |
