"BitCoinJ implements the "simplified payment verification" mode of Satoshis paper. It does not store a full copy of the block chain, rather, it stores what it n

"BitCoinJ implements the "simplified payment verification" mode of Satoshis paper. It does not store a full copy of the block chain, rather, it stores what it needs in order to verify transactions with the aid of an untrusted peer node." one click * HN user base = global time saving :)