The JVC GY-HM600 supports an SDXC memory card which is better than the SDHC memory card supported by most small sensor size camcorders that have been around for the last year. SDXC cards are SD cards but with a much higher capacity and faster processing speeds. They have a maximum capacity of 2TB (Terabytes).
This camcorder's memory card type (SDXC) is actually the best supported memory card type amongst all comparable spec camcorders that were launched in the last 12 months.
An SD memory card is the worst supported memory card type across comparable types of camcorder.
SDHC cards are DS cards with a higher capacity of up to 32GB.