What seems to be one prim...
... is actually four. These were made by turning on Copy Selected in the Create menu. Whichever face of the target prim you touch will align perfectly with the new prim. Be sure Center is turned on and Rotate is turned off. You can copy entire houses this way.
Copying An Object [Level II]
Second Life’s permissions system allows yourself to make infinite copies of any object you create—and many object you’ll buy or get for free will have copy permissions.
When you pull a copyable object from our inventory to the ground or (if it’s transferrable) give it to another person, it will remain in your inventory—so there’s no need to keep more than one copy in your inventory. If it’s a non-copy transferrable object, however, pulling it to the ground or giving it to someone will remove it to your inventory.
To make multiple copies of an object you can, of course, pull it multiple times from your inventory—but there are two easy ways to duplicate it. Both are simple.
Find some land where you can build and rez a prim or pull a copyable couch or airplane from your inventory. Then right click it and select Edit.
With the object selected you can, of course, use the red, blue, and green arrows to drag it about—but try holding the shift key and dragging the selected object 5 meters or so. Voila! You’ve moved the object, but yet it remains where it was. There are two now! You’ve made a copy!
We’ll leave it to you to figure out which is the original and which is the copy!
Now let’s try another method. Rez a simple prim cube.
Now right click it and select Create.
If you look carefully, you’ll see a box that reads Create Copy. Check that box. Be sure the box that reads Center Copy is also checked. Now touch the top or one side of your cube. Presto! A copy appears!
But not only has a second cube appeared, the side that touches is perfectly aligned with the first prim!
If you’re like me you’ll be jumping up and down with excitement about now. So THAT’S how builders are able to line up their prims! You’re smiling, thinking of how much easier it will now be to build a wall or a floor.
When you’ve finished playing be sure to uncheck Copy Selection; otherwise, when you try to rez a prim nothing will happen—unless you have a copyable object selected, in which case you may find a second copy of your house intermeshed with the original!