Every object (including players, rooms, exits) has a name and a bunch of aliases. This allows one to name an object formally (eg. "christmas") but also be able to refer to it using a nickname (eg. "xmas").
Aliases also provide a more useful function. If an object were called "the space station" and had no aliases, one wouldn't be able to type "look station" or "look space" since the name starts with "the". Whenever a name has multiple words in it, one should add aliases for each substring. Therefore "the space station" should have "space station" and "station" as aliases.
There is no point in making an alias be a prefix (the first few letters or word) of a name since it will have no effect on the matching process. An object called "the space station" could be refered to as "the space" or even "t" without any aliases.
Help is available on the following commands:
?@rename? -- change the names or aliases of an object or yourself.
?@addalias?, ?@rmalias? -- add and remove aliases.