These models - from companies like JVC & Sony - use Flash Memory cards to save MPEG-2 and MPEG-4 video clips to a high-capacity card much like those that are used in your digital stills camera, only they can hold much more information and can write/read data much more quickly. Formats like Panasonic's SDR, or Sanyo's Xacti models, are gaining in popularity as the capacity of the SD cards (etc) increases to the equivalent of large DVD disks, although the ease with which the recorded clips can be edited accurately is similar to DVD and HDD recordings (they use the same type of compression systems, after all).