LinuxMCE's main concepts are Devices, Events, and Activities (aka Scenarios, Command Groups, etc). An Orbiter refers to the user interface, be it on a media station, web pad, mobile phone, etc.
'Devices' A device is some piece of hardware or software, like the Xine Media Player, the light switch in the bedroom, or your mobile phone. All devices do 3 things: 1) Retrieve configuration data 2) Respond to commands, like turn on, turn off, fast forward, etc., 3) Fire events, like 'motion detected', 'playback started', etc.
'Activities' Activities, scenarios and command groups are interchangeable and all mean the same thing. This is really just a group of commands that get sent to a device. In LinuxMCE, your main menu consists of a several activities, grouped by room, and categorized as Lighting, Media, Climate, Telecom and Security. All the activities do the same thing: send commands to devices. The categories lighting, media, climate, telecom and security are arbitrary and just for convenience so it's easier to find the activity you want. Whenever you tell LinuxMCE to do something, it's always by choosing an activity from the main menu on an Orbiter. LinuxMCE creates lots of default, common activities for you automatically. For example, in any room where you have both a TV and some lights, LinuxMCE automatically creates an activity called 'Showtime' that dims the lights to 10%. In any room where you have a PVR or other TV-enabled device, it creates a scenario called 'TV' in the 'Media' category that starts the TV system. It also creates a command in the 'Media' category called 'Video' that sends a command to the Orbiter GUI telling it to display all your video content. Activities are automatically created under Telecom to make phone calls, and under Security to view cameras and arm your alarm.
These are just default activities. You can have a fully-functional system and do almost everything using only the default activities. If you want to change or remove some default activities, or add your own, do it using the admin web page, under Wizard, Scenarios. Note that when creating an activity, or scenario, the web page will give you a wizard that's most appropriate based on the category you picked. So if you're adding an activity in the lighting category, the wizard will show you all your lights and let you pick which ones to turn and off. If you're creating an activity in the security category, it will show you what cameras you have, and selecting that activity on the orbiter causes it to show the camera.
Remember the categories, and the wizard, are just for convenience. Any activity can send any command to any device. So, when you're adding an activity in the lighting category, although by default the admin site will only show you lights, if you click the 'Advanced Wizard' option you'll see that as part of that activity you could send any command to any device. You could make a phone call, for example, using an activity in the lighting category.
The grouping by room is also for convenience, and doesn't restrict the activity to only controlling devices in that room. So if your kitchen is near the garage and you want an activity 'turn off the garage light', you can put that activity in the room 'kitchen', and not in the room 'garage' if it's something you would normally want to do while you're in the kitchen. It doesn't matter that the light you're controlling is in the garage. You tell each Orbiter which room it's in, and it will always show you the activities for that room. The orbiters, or user interfaces, that appear on the tv and which you control with a remote control, will be by default in the same room as the media station is. You probably won't ever change this because that media station is generally in a fixed place. Something like a webpad, however, may be carried throughout the house. So, whenever you enter a room, note the 'Room' at the bottom of the screen and confirm it really is the room you're in. Otherwise you will see the activities from another room. And this may be confusing. Both the Living Room and Bedroom may have an activity 'TV'. You have a web pad that is in the Bedroom, and carry it to the Living Room, and forget to tell the web pad it's now in the Living Room, and notice that at the bottom of the screen it still says 'Bedroom'. So you hit the 'TV' button expecting the Living Room TV to come on, when in fact you're still controlling the bedroom.
Once you get used to this concept, however, you'll find it's very convenient. Because every orbiter, be it the one on the TV, the web pad, the pda, the mobile phone, etc., can be set to be in any room and choose activities from that room. And every orbiter has the exact same activities for each room. You do not create activities for one orbiter and not another. The activities are grouped by room--not Orbiter. So whether you pick up your mobile phone, your web pad, or your remote control, when you're in the Living Room, you will have the same list of options for the Living Room.
To prevent some family members from using some activities, use the admin web panel to lock down which rooms an Orbiter can switch to. Maybe the Orbiter that is on the desktop phone in little Suzy's bedroom will be locked to only be able to switch to her room and to the living room. That means she can execute the activities in her room, like 'go to sleep' which may turn off her lights, and in the living room, but her Orbiter won't let her switch to the Master Bedroom and choose the activities in that room. You can also say that a pin code is required to switch an orbiter into a certain room, so the whole family can share a web pad as an orbiter, and the kids can use it in the living room to watch tv, but they cannot switch it the master bedroom and run the activities in that room without entering a pin code.
'Events' Remember devices send off events, like 'Playback started', 'Motion Sensor tripped', and so on. The normal way in LinuxMCE to do something is, as mentioned, to create an activity that you select from an Orbiter. But if you want something to happen automatically without the user doing something, you can create Event Handlers. For example, you can create an event handler that listens for the 'Motion Sensor tripped' event from a motion detector and in response turns on some lights. Or an event handler that listens for the 'Sunrise' event which the event plugin sends every time the sun comes up, and make it do certain things in response too.
Just like LinuxMCE creates some default activities for you, it also creates some default event handlers. For example, in any room where you have a TV and lights, it not only creates a Showtime activity, it also creates an event handler that listens for the 'Watching Media' event from any media player in that room, and executes the Showtime scenario automatically. This means that whenever you start a movie, the Showtime activity is executed, which be default dims the lights. There are also some default event handlers to intercept events like 'Security Breach' and 'Fire Alarm' from your home's security system and respond with default behavior.
'Controlling an Orbiter' To control the system, you use any orbiter, which is just LinuxMCE's term for a remote control. All Orbiter's have the same basic function: to display all the activities in whatever room you're in and let you pick the one you want. The different Orbiter's may display this slightly differently depending on their screen size, but the function and the list of activities is always the same. The normal UI1 interface which you'll use on webpads and pda's, displays all the activities in a room in horizontal rows. Just pick the one you want and it's executed. If there are more than will fit on a row, you'll have a more button. If you're ont already at the main menu, there is generally a home button that takes you there. On small displays, like mobile phones and desktop phones, there's not enough room to show the activities themselves, so the top level menu typically just shows you the categories: Lights, Media, Climate, Security and Telecom. You pick a category to see the activities in that category.
UI2, which is the preferred user interface for the media stations, displays all the categories along the bottom of the screen, and the activities in that category popup vertically, like a pull-down menu in a pc, except upside down. You can use either an infrared remote, or a mouse, or a keyboard to navigate the menu. If the main menu isn't already visible, bring it up by pressing