input: [Explanation] A proposed add-on function for bitcoin that would enable bitcoin users to give them additional attributes. These attributes could be user-defined, enabling you to mark a bitcoin as a share of stock, or a physical asset. This would enable bitcoins to be traded as tokens for other property. [Term] 
output: Colored coins
options: C o n f i r m a t i o n
options: C r y p t o g r a p h y
options: C i r c l e
options: C l i e n t
options: C o l o r e d c o i n s
options: C P U
options: C o i n b a s e
options: C o i n a g e
options: C r y p t o c u r r e n c y