look <person>'s <object>
The look command shows the enactor the description of the object, and the visible items inside the object if the object does not have the Opaque flag set.
If no object is specified and the enactor is in a room, look shows the description, contents, and exits of the enactor's location unless the room has the Dark flag, in which case the exits and contents are hidden (except for those that have the Light flag set).
If no object is specified and the enactor is in a thing or player, the idescribe and contents of the enactor's location is shown.
You can usually look at another player or thing's inventory by using the possessive form of the command. Setting the Opaque flag on an object prevents people from looking inside it.
look/outside can be used from inside a thing or player to look out at your container's location. Again, the Opaque flag prevents people from looking outside of an object.