Mobile High-Definition Link is a standard for connecting mobile and portable devices to HD displays such as TVs and monitors. Like HDMI, it uses a single cable to transmit 1080p HD video and up to 7.1 surround audio, but it also adds the capability to power and charge the mobile device.
MHL commonly uses a micro USB connection at one end and an HDMI connector at the other, although others can be used as no specific physical connectors are mandated by the standard. This sometimes leads to incompatibility, as is the case with Samsungs Galaxy S II and Galaxy S III phones, which require different MHL cables to work.