SecureChat performs a RSA 2048 with Optimal Asymmetric Encryption Padding (OAEP) on chat messages with Personal and Public certificates, thus no one can read them, except the participants.
SecureChat for Skype is an ultimate and convenient assurance for you, to have private and secured chat conversations, so you'll not get spied, eavesdropped, tapped as you chat to someone from your contact list. More Info »
Imagine even the simplest example - you did accidentally forget Skype signed in on some of your home or work computers and you are chatting by other devices, so everyone who has access to your computer could just look at your chat sessions, while you chat to someone else.
Securechat even helps against hackers, who would steal your Skype password and they could do the same all the time, without you even suspecting this could be happening.
So have your peace of mind, whenever you want privacy, do it the right way just start SecureChat's encryption on.