ExpressCards are smaller, lighter, and faster plug-in cards that were introduced by the PCMCIA people in 2003. In addition to all the services available through PC Card sockets, an ExpressCard socket can also support the latest USB and PCI-Express connections. As Figure 24.3 shows, ExpressCards exist in two sizes, 34 mm wide and 54 mm wide. Both sizes use the same 26-pin connectors, so an ExpressCard/54 (54 mm) socket accepts both types. ExpressCards are not yet common, but many laptop manufacturers, including Fujitsu, NEC, Sony, Lenovo, Toshiba, and Dell have all begun to include ExpressCard slots in their new laptop computers.
Figure 24.3: ExpressCards are shorter and narrower than PC Cards.
If your laptop does not include an ExpressCard socket, don't worry (yet); it should be possible to find a PC Card or a USB device that performs the same function as any currently available ExpressCard. Or if you prefer, you can look for an external ExpressCard reader that connects to your computer through a USB port.