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