Acronym for Dynamic Link Library, a library of executable functions or data that can be used by a Windows application. A DLL can be used by several applications at the same time. Some DLLs are provided with the Windows operating system and available for any Windows application. Other DLLs are written for a particular application and are loaded with the application.

Acronym for Enhanced MetaFile. A newer 32-bit version of Windows MetaFile. EMF contains frame information and contain more drawing commands then its predecessor, WMF.

Acronym for Portable Network Graphics. PNG is a bitmap image format that employs lossless data compression.

Acronym for Rich Text Format. A document file developed by Microsoft since 1987 for cross-platform document interchange. Most word processors are able to read and write RTF documents.