The X
按字母分类：
extension name file type Classification
RAD Radar ViewPoint Radar Data text file
README Readme File text file
RFT Revisable Form Text Document text file
RIS Research Information Systems Citation File text file
RPT Generic Report text file
RST reStructuredText File text file
RTD RagTime Document text file
RTF Rich Text Format File text file
RTFD Rich Text Format Directory File text file
RTX Rich Text Document text file
RUN Runscanner Scan File text file
RVF RichView Format File text file
RZK File Crypt Password File text file
RZN Red Zion Notes File text file