The UDF file extension is used to refer to script files written in the Visual Basic programming language. UDF files can be accessed and edited with the appropriate software.The UDF extension is also used to signify Universal Disk Format files that are used to organize files on optical media devices like readable and writeable CDs.
Microsoft Excel allows users to create their own user-defined functions. Using the power of Visual Basic for Applications (VBA), you can code complicated formulas only once and use them again and again in your spreadsheets and workbooks. These functions can be used just like any built-in function already available in Excel.
The UDF file extension is associated with the Microsoft Visual Studio programming and development suite for Microsoft Windows. The .udf file stores user defined function script for the SQL database.
X-ray Diffraction Data File Format