| elc | Emacs Lisp Compiled Bytecode |
| eld | EasyLanguage Document |
| elf | Executable and Linkable Format File |
| elk | Altium Designer Linker Error Messages File |
| els | EasyLanguage Storage |
| emakefile | Erlang Makefile |
| emat | ANSYS Element Matrix Data |
| emcl | microC Library |
| emma | EMMA Data File |
| emma | Extensible MultiModal Annotation Markup Language Data |
| emof | Eclipse EMOF Model |
| emx | IBM Rational Software Architect Model |
| enigma | Enigma Protector Data |
| enigma64 | Enigma Protector x64 Data |
| entitlements | App Sandboxing Entitlements |
| ephtml | Enhanced Perl-parsed HTML |
| epl | TallyMan EPL File |
| eql | Embedded SQL |
| erb | Ruby ERB Script |
| erb | Erubis Script |
| erbsql | Ruby ERB SQL Script |
| erc | Ercato Engine Code |
| erd | Active Media Eclipse Data |
| erl | Erlang Source Code |
| erlang | Erlang Source Code |
| ers | Altium Designer Assembler Error Messages File |
| erubis | Erubis Script |
| es | Sage CRM Script |
| es | ECMAScript Source Code |
| es4 | ECMAScript 4 Source Code |