This is a Pidgin plugin which implements Off-the-Record (OTR) Messaging.
OTR allows you to have private conversations over IM by providing:
* Encryption.
* No one else can read your instant messages.
* Authentication.
* You are assured the correspondent is who you think it is.
* Deniability.
* The messages you send do not have digital signatures that are checkable by a third party. Anyone can forge messages after a conversation to make them look like they came from you.
However, during a conversation, your correspondent is assured the messages he sees are authentic and unmodified.
* Perfect forward secrecy.
* If you lose control of your private keys, no previous conversation is compromised.