My new Pocket PC has both CompactFlash (CF) and Secure Digital (SD) slots. Are they basically the same? Can I use them for the same purposes?
Several Pocket PC models—including ones from Casio, NEC, and Toshiba—have both types of expansion card slots. Each slot accepts flash memory cards to expand your device's program and document storage. If you'll be using your PDA with a variety of accessories—or even if you think you might—use the SD slot for memory cards and reference data and reserve the CF slot for peripherals.
Right now, the majority of expansion-card–based PDA accessories, such as modems, network interfaces, cameras, and GPSs, are available in CF format. Eventually, peripheral makers will release SD models in equal number, but we recommend you use SD for memory expansion and free up the CF slot for other purposes. The downside here is that SD memory costs about twice as much as CF per megabyte. But the added flexibility is worth the extra expense.