The DXF file format was created by Autodesk in 1982 and the intention was to create a format that was independent of CAD applications and therefore eased the difficulties of sharing files created by different applications. This was particularly important for early versions of CAD as reverse engineering of the closely guarded DWG format was limited. However in recent years the usefulness of DXF format has reduced due to DXF not being able to support more advanced CAD elements such as dynamic blocks. The market leading popularity of AutoCAD has also reduced the requirement for an application independent format.
DXF files are organised in way that allows the files to be opened by a normal text editor application.vA DXF file has a common format containing a number of sections. These include the Header which contains file property information, Classes, Tables, Entities, Blocks and Thumbnail Image section. The data contained within a DXF is known as tagged data which means that the tags identify how the data should be interpreted. For example there are a large number of group codes related to the creation of an ellipse. Various group codes allow for the definition of the start and end points, centre point and extrusion directions.
Adobe Illustratror AutoCAD CorelCAD Open Office PaintShop Pro
PDF is a file format developed by Adobe Systems for representing documents in a manner that is separate from the original operating system, application or hardware from where it was originally created. A PDF file can be any length, contain any number of fonts and images and is designed to enable the creation and transfer of printer-ready output.
Each PDF file encapsulates a complete description of a 2D document (and, with the advent of Acrobat 3D, embedded 3D documents) that includes the text, fonts, images and 2D vector graphics that compose the document. They do not encode information that is specific to the application software, hardware, or operating system used to create or view the document.