1. What is GNUstep

GNUstep can mean manu things, depending on whether you are a developer or a user. In a general sense, GNUstep is a set of libraries that provide a way for developers to write advanced, cross-platform desktop applications. It is not an application or a program in itself. Instead, it provides a number of services for building and running applications written to take advantage of it.

It is cross-platform, meaning it runs on many different types of computers and operating systems. It runs on Linux, MacOS X, Windows, most BSD derivatives such as FreeBSD, OpenBSD and NetBSD, Solaris, and many other Unix-like operating systems.

For users, it provides a clean, integrated Graphical User Interface (GUI) for running applications on. For developers, it provides an advanced object-oriented framework for true cross-platform application development that is logical and simple to use.

It is based on the OpenStep standard published by NeXT (now Apple Computer Inc) in late 1994, and has evolved to track it's now present commercial implementation, MacOS X's Cocoa framework. If you've used Cocoa for development, you'll be right at home with GNUstep, which offers a high-degree of source-level compatibility for your code.

The standard GNUstep installation is split into four parts, of which must be installed in order and are all required if you plan to run GNUstep applications or perform GUI development.

1. gnustep-make This is the makefile package that provides a common set of makefiles and install scripts for easily deploying applications across platforms. It sets up the GNUstep directory hierachy and installs the Makefiles needed for tool and application development. For developers, this would have to be one of the easiest makefile systems to use on the planet.

2. gnustep-base This is a libary that provides the low-level base services need in virtually all applications. It's quite advanced, providing the usual things for developers such as strings, arrays and dictonaries, time and date support etc, but also more complex things such as distributed objects and XML support. These are integrated right at the language level, and such are very natural and easy to use and are handled the same on different platforms.

3. gnustep-gui This is the library that provides the higher-level graphical user interface services needed in desktop applications. You'll want to install this if you want to run graphical GNUstep applications (such as GWorkspace or GNUmail).

4. gnustep-back This library is needed by gnustep-gui so that it can render applications onto your screen. It provides the necessary glue to work with the X Window System and Windows GDI.