The USB (Universal Serial Bus) standard has been around since the mid 90’s, and ever since the late 90’s it has been practically an impossibility to buy a PC without half a dozen USB ports on the systems motherboard, let alone the extra ones connected onto the case itself (of course they’re internally wired onto the motherboard too).
There have been numerous additions to the USB standard, USB 2.0 taking things up to a nippy (for then at least) 30 – 40 MB/s range. USB 3.0 improved things significantly however, and you’re looking at about 500MB/s (real world performnce, of course your mileage may vary depending upon the device).
TomsHardware have taken an in-depth look at USB 3.0 and the various standards. It could be worth your time reading it if you’re thinking of either buying say a new USB harddrive, or upgrading your PC at any point in the near future. At the very least, it’s an interesting read for those of you who share an interest for the tech side of things.