[1] Unlike emoticons, they are not text art, and instead describe the action using words or images (similar to emoji).
In online chatrooms that do not support the "/me" command, it is conventional to read text surrounded by asterisks as if it were emoted.
For example, reading "Joe: *jumps with joy*" in a chat log would suggest that the user had intended the words to be performed rather than spoken.
[2] In MMORPGs with visible avatars, such as EverQuest, Asheron's Call, Second Life and World of Warcraft, certain commands entered through the chat interface will print a predefined /me emote to the chat window and cause the character to animate, and in some cases produce sound effects.
For example, entering "/confused" into World of Warcraft's chat interface will play an animation on the user's avatar and print "You are hopelessly confused."