Glad you asked. For years, the standard has been known as HD-SDI (high-definition, serial digital interface). This has been referred to as SMPTE 292M, providing a nominal data rate of 1.485 Gbits per second. Then came the dual link HD-SDI interface consisting essentially of a pair of SMPTE 292M links, standardized in SMPTE 372M, providing 2.97 Gbits per second. Some applications, such as Digital Cinema, requiring greater fidelity and resolution than the standard HDTV provided, embraced this evolution. Always wanting to improve the way we do things, the 3G-SDI interface was created. This interface consists of a SINGLE 2.97 Gbit per second serial link and is standardized in SMPTE 424M. Why 3G? This interface supports 4:4:4 at 2K resolution on ONE BNC. It’s a breakthrough.