input: [Explanation] A software program running on a desktop or laptop computer, or mobile device. It connects to the bitcoin network and forwards transactions. It may also include a bitcoin wallet (see node). [Term] 
output: Client
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