The sendTones() method of the Telephony Interface generates multiple DTMF tones, with a specified duration for each tone, and an optional delay before generation starts. The tones are sent to the currently active call.
The <audio> and <video> elements provide support for playing audio and video media without requiring plug-ins. Video codecs and audio codecs are used to handle video and audio, and different codecs offer different levels of compression and quality. A container format is used to store and transmit the coded video and audio (both together, the case of a video with a soundtrack). Many combinations of codecs and container formats exist, although only a handful of these are relevant on the Web.