The Panasonic HS900 supports an SDXC compatible memory cards which is better than the SDHC compatible memory cards supported by most video cameras of a comparable spec and age to it. In addition, this camcorder supports an SD compatible memory cards. 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 compatible memory cards is in fact the best supported memory card type amongst all comparable spec camcorders that are a similar age to the HS900.
The worst supported memory card type across similar types of video camera is MicroSD (Transflash).
SDHC cards are DS cards with a higher capacity of up to 32GB.