Electrum is a lightweight Bitcoin client written in Python
Project page: http://electrum.org/
Electrum is a lightweight Bitcoin client written in Python. It does not store the blockchain so disk usage is minimal. Electrum only stores block headers to ensure that it is connected to nodes using the same blockchain and verifies that the headers have valid PoWs. In order to get data about transactions, Electrum must connect to special full nodes running an Electrum server software.
Questions under this tag should be about the usage and development of Electrum.