Before you get a problem in working with your computer then you move over to other computer, or you want to move your documents to the new computer. You may check these file extension lists that need to backup:
Microsoft Office Word and Word Processor family:
* docx ( Modern Microsoft Office )
* odt ( Modern FOSS Office )
* doc ( Classic Microsoft Office )
* rtf ( inter compatibility file format )
* wps ( WPS Office )
Microsoft Office Excel:
* xlsx ( Modern Microsoft Office Excel )
* xls ( Classic Microsoft Office Excel )
* csv ( inter compatibility file format )
* ods ( Modern FOSS Office )
Microsoft Office PowerPoint:
* pptx ( Modern Microsoft Office Presentation )
* ppt ( Classic Microsoft Office Presentation )
* odp ( Modern FOSS Office )
Microsoft Office Access:
* accdb ( Modern Microsoft Office Access )
* mdb ( Classic Microsoft Office Access )
* mdw ( Modern Microsoft Office Access )
* mda ( Classic Microsoft Office Access )
Image / Photo format:
* jpg ( inter compatibility graphic)
* bmp ( inter compatibility graphic format)
* Raw Camera Format ( for example: Canon cr2, cr3; Nikon nef, Sony arw, Fuji raf )
* tiff ( inter compatibility raw graphic format )
Video format:
* avi ( Windows video format )
* mov ( Apple QuickTime video format )
* mp4 ( Digital video format )
Lightweight document format :
* md ( markdown )
* rst ( restructured text )
* adoc ( asciidoc )
* bbcode ( buletin board )
* wiki ( wikitext )
* txt ( text file )
Ebook format :
* pdf ( Adobe proprietary format )
* epub ( open collaborative publisher format)
* azw ( Amazon proprietary format )
* mobi ( Amazon Mobipocket ebook reader )
Archive And Business Files format :
* 7z ( Compressed archive file )
* ics ( Calendar of Event file format )
* rar ( Compressed archive file )
* vcf ( Digital Business contact file )
* zip ( Compressed archive file )