Large, fast drives are good, but you still have to get the data on and off the drive. The connector, or the data bus, is what moves the data between the drive and your computer. Hard disk drives with faster connector types, or more connector types, are more expensive. The most common connector types (from slowest to fastest) are:
One note: Universal Serial Bus (USB) is the most common connector interface used for connecting external devices to computers. USB 1.0 is the slowest, eSATA is a modified version of the internal connector interface used with hard disk drives and most computer systems today. If your computer doesn’t have an eSata or Firewire port, it is useless to buy a drive that only has those types of ports because you can’t plug it in. Most drives have a USB port, but be certain it is a USB 2.0 or better port.