A Channel is basically the same thing as a television channel. The Channels show Watchers what they suscribed for. Channels are usually paid for, but there exists a Free Channel.
Also, each LiFe character can be a channel. There are 3 angles from which Watchers can view the personal channel. They are above the head, over the shoulder, and around the waist. The second angle uses less bandwidth then the other 2. There are privacy settings that characters can use to determine where and when people can watch their channel. Each group in the Game has their own channel, as well.
A channel in LiFe is different than the channel for the same person in The Game. This can be seen with Danni Morretti's channel. As Kleya and Danni walk to enter Sandra's server for the first time, The Bandit is seen watching Danni's channel. However, as soon as Danni leaves LiFe and begins to load into The Game, her channel said "End of Danni Morretti's Channel. User Danni Morretti has logged out of L.i.F.e. You will be updated when she returns."