SATA II is the next set of SATA specifications after the initial SATA specification was written. SATA II specifications provide additional enhancements to SATA, delivered in increments. The first increment, called .SATA II: Extensions to SATA 1.0. was released in 2002 and focused on the immediate needs for the server and network storage segments. Additional increments of the specification will focus on enhanced cabling, fan-out and failover capabilities and next generation signaling speeds. In spring 2003, two incremental developments were announced: a SATA II Port Multiplier specification release candidate and the completion and pending adoption of the SATA II Cables and Connectors Volume 1 specification. [Source: Serial ATA.org]
See also SATA.