Off-The-Record messaging (short: OTR) is a cryptographic protocol to encode real time communication like chatting or instant messaging. It authenticates communication partners, encrypts messages, as well as renders impossible any way to find out which key was used by whom. As a result, a specific message cannot be traced back to a specific person – this (feature) is called deniability. Another feature of OTR is the random combination of keys, which is automatically destroyed after their final use. As soon as the keys are deleted, the interchanged messages cannot be deciphered anymore.