The two most common types of files in an EGL project are source files and build files. EGL also uses deployment descriptors in service applications and service client applications.
Source files contain EGL source code in units called logic parts and data parts. You can have any number of logic parts and data parts in any one source file, except that you can have only one main part in a source file.
Source files have an extension of .egl and are written in EGL source format.
Build files contain information EGL uses to generate and deploy applications. Build files are written in Extensible Markup Language (XML) and have the extension .eglbld. This type of file contains build parts such as Build Descriptor parts, linkage options parts, and resource associations parts.
Whenever possible, use the build parts editor provided in the workbench to work with build parts and build files. However, it is possible to edit a build file with a text editor or XML editor.