Many common Skype activities expose data that is not encrypted at various points between two users.
Skype Private Conversations give you enhanced security through end-to-end encryption with an additional layer of security for conversations between you and your friends and family.
The company announced the experimental feature named "Private Conversations" in a blog post today. Microsoft said that after its round of testing is complete, the company would work to integrate Private Conversations into the UWP version of Skype that ships as part of Windows 10.
The key difference between the new feature and its typical chats is that users must specifically accept invitations to private conversations. End-to-end encryption means not just the communication channel is secure but the messages stored on servers can only be read by those involved in the communications. The encryption will cover chat, files, and audio messages, but not audio or video calls. We also send freebies and lots of other goodies exclusively to our email subscribers.
After you're done talking, you can delete the Private Conversation if you believe it's not worth keeping.
A Private Conversation will have a lock icon next to your contact's name.
It is important to note that no chat content from these conversations will be displayed in the chat list, or with other notifications - in order to keep any shared information private. The conversation can be switched to any device being used at the time but the messages sent and received will be tied to the device being used at the time. Encrypted conversations are locked to the device they are started on.