Files with CSV (Comma Separated Values) extension represent plain text files that contain records of data with comma separated values. Each line in a CSV file is a new record from the set of records contained in the file. Such files are generated when data transfer is intended from one storage system to another. Since all applications can recognize records separated by comma, import of such data files to database is done very conveniently.
Files with WMF extension represent Microsoft Windows Metafile (WMF) for storing vector as well as bitmap-format images data. To be more accurate, WMF belongs to the vector file format category of Graphics file formats that is device independent. Windows Graphical Device Interface (GDI) uses the functions stored in a WMF file to display an image on the screen.
You can also convert CSV into many other file formats. Please see the complete list below.