The three buttons [.] [\] and [^] select point, line or face editing respectively when Anim8or is in "point edit" mode.
They're the second row below the xyz motion control buttons.
The UV button selects Anim8or's surface texture editor. It's rather crude, though. There are stand-alone Windows programs that are better for applying surface textures to models. (Anim8or does let you apply textures to individual faces, but Celestia does not support that.)
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