User-Defined Function (Microsoft Excel)
UDF is a user-defined file format for Microsoft Excel. UDF stands for User-Defined Functions. UDF files are made using Visual Basic for Applications and allow the user to create custom functions which can be used repeatedly on numerous spreadsheets and work books. UDF files can be created in Excel by selecting the “Module” option in the “Insert” menu.
MIME: application/excel, application/x-excel
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