Original: Modern, Internet-wide, GUI-based messaging clients, as they are known today, began to take off in the mid 1990s with PowWow, then ICQ, followed by AOL Instant Messenger (AOL Instant Messenger, 1997).
Simplified: Modern, Internet-wide, GUI-based messaging clients, as they are known today, began to take off in the mid 1990swith ICQ (1996) being the first, followed by AOL Instant Messenger (AOL Instant Messenger, 1997).