It can be used in several ways:
* To vanish completely: "The magician disappeared in a puff of smoke."
* To become hidden or lost: "My keys have disappeared again."
* To stop existing: "The dinosaurs disappeared millions of years ago."
* To leave without notice: "He disappeared without a trace."
"Disappear" can also be used figuratively to describe things that are no longer relevant or important: "The old technology has disappeared."
It's important to note that "disappear" can have a negative connotation, implying that something is lost, missing, or gone forever.