Python is an interpreted, interactive, object-oriented programming language. It combines remarkable power with very clear syntax, and isn't difficult to learn. It has modules, classes, exceptions, very high level data types, and dynamic typing. There are interfaces to many system calls and libraries, as well as to various windowing systems (Tk, Mac, MFC, GTK+, Qt, wxWindows). New built-in modules are easily written in C or C++. Python is also usable as an extension language for applications that need a programmable interface.
Ghostscript is a processor for PostScript and PDF files. It can rasterize these files to a wide variety of printers, devices for screen preview, and image file formats. Since applications tend to prepare pages for printing in a high-level format such as PostScript, most Unix users with low-level bitmap printers, such as inkjets, use GhostScript as part of the printing process. In addition, Ghostscript is capable of converting PostScript files, functionality comparable to Adobe Acrobat Distiller, but on the command line. In addition, Ghostscript is used for file import and viewing by a great many other applications, including xv, ImageMagick, gimp, and xdvi. Several GUI wrappers for viewing PostScript and PDF files exist, including GSview, ghostview, gv, ggv, and kghostview. This is far from a comprehensive list.
Frink is a calculating tool and programming language designed to help you in the real world. It tracks units of measurement throughout all calculations and ensures that answers are correct. It converts between systems of measurement, and has a huge library of physical data. It is both a simple calculator for quick calculations and a full-fledged programming language for large tasks. It draws high-quality graphics, handles conversions between time zones, currencies, and historical values of the U.S. dollar and the British pound, translates between several languages, does date/time math, and more.
Lua is a programming language originally designed for extending applications, but also frequently used as a general-purpose, stand-alone language. It combines simple procedural syntax (similar to Pascal) with powerful data description constructs based on associative arrays and extensible semantics. It is dynamically typed, interpreted from bytecodes, and has automatic memory management, making it ideal for configuration, scripting, and rapid prototyping. It is implemented as a small library of C functions, written in ANSI C, and compiles unmodified in all known platforms. The implementation goals are simplicity, efficiency, portability, and low embedding cost. It has been used on games such as World of Warcraft, FarCry and Angry Birds, among others.
SableCC is a parser generator that generates fully featured object-oriented frameworks for building compilers, interpreters, and other text parsers. In particular, generated frameworks include intuitive strictly-typed abstract syntax trees and tree walkers. SableCC also keeps a clean separation between machine-generated code and user-written code, which leads to a shorter development cycle.
Apache::ASP provides an Active Server Pages port to the Apache Web Server with Perl as the host scripting language. Apache::ASP allows a developer to create dynamic Web applications with session management and embedded Perl code. There are also many powerful extensions, including XML taglibs, XSLT rendering, and new events not originally part of the ASP API.
GNU ccScript offers a class extensible threaded embedded scripting engine for use with the Common C++ GNU package. This engine is also used in Bayonne (the GNU telephony server), and in TOSI (FreeBSD and GNU/Linux PBX integration servers). This engine differs from traditional scripting systems in that it is used to script near real-time state-event systems through deterministic callback step execution rather than the linear and non-deterministic fashion of embedded script libraries such as tcl, and libguile.
Squirrel is a light-weight programming language (around 6000 lines of code) that features higher-order functions, classes/inheritance, delegation, tail recursion, generators, cooperative threads, exception handling, reference counting and garbage collection on demand. It has a C-like syntax.
Logtalk is an object-oriented logic programming language that can use most Prolog implementations as a back-end compiler. As a multi-paradigm language, it includes support for both prototypes and classes, protocols (interfaces), component-based programming through category-based composition, event-driven programming, and high-level multi-threading programming.