The JVC GY-HM850 supports an SDXC memory card which is better than most latest video cameras. Most small sensor size video cameras that have been around for a similar time to it support an SDHC memory card. SDXC cards are SD cards but with a much higher capacity and faster processing speeds. They have a maximum capacity of 2TB (Terabytes).
An SDXC memory card is actually the best supported memory card type across all video cameras that have been on the market for the last year.
An SD memory card is the worst supported memory card type across comparable types of video camera.
SDHC cards are DS cards with a higher capacity of up to 32GB.