What is V4L or DVB?
LinuxTV.org hosts both the Video4Linux (analog video) and DVB (digital TV) Linux subsystems.
Despite the fact that the two subsystems are very unique from one another, real world application often finds them closely intertwined in scope or context. As such, it is practical that the two are housed together, as it fosters a more efficient dissemination of content and, in general, makes for a more user friendly source of information. At the same time, this by no means undermines the fact that we are indeed dealing with two unique subsystems!
The Linux DVB API
The V4L2 API