Hard disk
Over the years there have been many disk interface types, though all used the same rotating platter recording technology.  Differences were in how the data was encoded to binary, data integrity, data transfer speeds, cabling requirements, and cost.  In 2009, it was common to attach a hard disk using a Serial ATA connection.  The connection that came before that was called "IDE" and is called Parallel ATA today.  In large data centers, Fibre Channel is often used.