The pc card and cardbus devices are being replaced by what technology?
A PC Card or PCMCIA is a credit card-sized memory or I/O integrated circuit device that adds peripheral functionality to a laptop computer. A PC card is not to be confused with a smart card, which contains an embedded microprocessor and is used for authentication and security purposes.
Developed by the Personal Computer Memory Card International Association (PCMCIA), PC Cards were most commonly used in portable computers during the 1990s to allow users to add hardware capabilities such as modems, network adapters and storage drives. Some laptops had a slot built into them to accommodate PC Cards, and most desktops could use PC Cards with an appropriate adaptor.
The older 16-bit and later 32-bit PC Card design used a serial data interface that connected to the host system bus via a PCI connector. The connector had a slight notch on the front to differentiate it from earlier equipment that only supported 16-bit devices, and the CardBus version of the specification added support for higher data transfer rates of up to 33 MB/s in byte mode and 66 or 132 MB/s in word or double-word modes.
Eventually, the PC Card standard was supplanted by the more advanced ExpressCard and USB technologies. Today, notebooks are fitted with ExpressCard slots instead of the older PC Card slots and most expansion features that were available as a plugin module for laptops now exist in the form of external USB devices.