即時通訊
Secure instant messaging is a form of instant messaging. Both terms refer to an informal means for computer users to exchange messages commonly referred to as "chats". Instant messaging can be compared to texting as opposed to making a mobile phone call. In the case of messaging, it is like the short form of emailing. Secure instant messaging is a specialized form of instant messaging that along with other differences, encrypts and decrypts the contents of the messages such that only the actual users can understand them.