Source : Free On-Line Dictionary of Computing

Double Data Rate Random Access Memory
     
         (DDR-RAM, DDR-SDRAM ...Synchronous...) {RAM} that
        transfers data on both 0-1 and 1-0 {clock} transitions,
        theoretically yielding twice the data transfer rate of normal
        RAM or {SDRAM}.
     
        {DDR-RAM Article
        (http://www.pcreview.co.uk/Article.php?aid=9)}.
     
        {DDR-SDRAM Article
        (http://www4.tomshardware.com/mainboard/00q4/001030/)}.
     
        (2001-05-24)