Channels are simply collections of content stored in one place. A channel can represent anything. It could represent you, a website, a forum, photo albums, anything. For most people, their first channel with be "Me".
The most important features for a channel that represents "me" are:
Secure and private "spam free" communications
Identity and "single-signon" across the entire network
Privacy controls and permissions which extend to the entire network
Directory services (like a phone book)
In short, a channel that represents yourself is "me, on the internet".
You will be required to create your first channel as part of the sign up process. You can also create additonal channels from the "Select channel" link.
You will be asked to provide a channel name, and a short nick name. For a channel that represents yourself, it is a good idea to use your real name here to ensure your friends can find you, and connect to your channel. The short nickname will be used to generate a "webbie". This is a bit like a username, and will look like an email address, taking the form nickname@domain. You should put a little thought into what you want to use here. Imagine somebody asking for your webbie and having to tell them it is "llamas-are_kewl.123". "llamasarecool" would be a much better choice.
Once you have created your channel, you will be taken to the settings page, where you can configure your channel, and set your default permissions.
Once you have done this, your channel is ready to use. At example.com/channel/username you will find your channel "stream". This is where your recent activity will appear, in reverse chronological order. If you post in the box marked "share", the entry will appear at the top of your stream. You will also find links to all the other communication areas for this channel here. The "About" tab contains your "profile", the photos page contain photo albums, and the events page contains events share by both yourself and your contacts.
The "Matrix" page contains all recent posts from across the matrix, again in reverse chronologial order. The exact posts that appear here depend largely on your permissions. At their most permissive, you will receive posts from complete strangers. At the other end of the scale, you may see posts from only your friends - or if you're feeling really anti-social, only your own posts.
As mentioned at the start, many other kinds of channel are possible, however, the creation procedure is the same. The difference between channels lies primarily in the permissions assigned. For example, a channel for sharing documents with colleagues at work would probably want more permissive settings for "Can write to my "public" file storage" than a personal account. For more information, see the permissions section.
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