This category is on programming languages with the proper name "E". So far, there are two, both Open Source. Wouter van Oortmerssen's Amiga E, an object-oriented, procedural, unpure functional language, common on Amiga. Main influences: C++, Ada, Lisp, etc. It has fast compiling, inline assembler, many integrated functions, strong modules, flexible types, quoted expressions, immediate and typed lists, parametric and object polymorphism, exception handling, inheritance, data-hiding, methods, multiple return values, default arguments, register allocation, fast memory management, unification, LISP-Cells, macro-preprocessing, powerful source code debugger, GUI toolkit, library linker, more. Description, readme, downloads, mail list. It is Freeware and Open Source. Mark S. Miller's E, a secure, distributed, pure-object platform and p2p (peer-to-peer) scripting language for writing capability-based Smart Contracts. It defines and implements a pure object model of secure distributed persistent computing. Its roots are Actor Model programming, KeyKOS operating system, and the Concurrent Prolog language. Kernel E is a minimalist lambda-language much like Scheme, and Smalltalk. These are some of the more potent and promising approaches and projects addressing security issues in software. It is Open Source.