DWG (“drawing”) is a format used for storing two and three dimensional design data and metadata. It is the native format for the AutoCAD Computer Aided Design package, as well as Intellicad (and its variants), and Power CAD. DWG is supported non-natively by several hundred other software applications. The name dwg stands for “drawing.” Other applications can open files saved as dwg.

The DXF file format is developed by AutoDesk and is used as a CAD file format. It was originally created as a way to increase interoperability between AutoCAD and other similar programs. The DXF file format was initially meant to provide exact representation of AutoCAD drawings which were natively stored in DWG(Drawing) format. The name dxf stands for “drawing interchange/exchange format.” The format was developed to allow applications without the ability to open dwg files to use the information contained within a drawing file.
While a dwg file retains all applicable layers, colors, line weights and x-references, a dxf file retains only information such as line work, dimensions and text..
When Should DWG be Used?
The dwg format is used when a drawing will be accessed only by AutoCAD or another program capable of opening the file with all of its components, such as certain versions of Google Sketchup.
When Should DXF be Used?
The dxf option should be used when a drawing’s basic elements, such as line work and text, need to be accessed, viewed and/or referenced by an application that is not capable of opening a .dwg file. Many applications can open a .dxf file in order to reference the included information but do not have the capability to open a fully functioning dwg file.
If you have a PDF file that you want to be able to edit in AutoCAD you will need to get that PDF into a CAD file for editing. If you need to convert a PDF into a CAD Drawing file, which is a DXF file, you can use a pdf to dxf converter to help. Aide pdf to dxf converter is a CAD converter that can take PDF files and convert them into DXF files that can be edited in AutoCAD. The program is easy to use and will quickly give you DXF files that you can edit. If you need trial that free, you can check out this page for convert pdf to dxf free
If you need to convert a PDF into a CAD Drawing file, which is a DWG, you can also use a program called pdf to dwg converter to convert the file easily and fast.