Linux supports a large variety of hardware devices such as mice, printers, scanners, PCMCIA and USB devices. However, most of these devices are not required while installing the system.
USB hardware generally works fine, only some USB keyboards may require additional configuration (see Section 3.6.4.4, “USB BIOS support and keyboards”).
Again, see the Linux Hardware Compatibility HOWTO to determine whether your specific hardware is supported by Linux.