Travel between star systems - which may someday be
do-able but given that even our closest star is
4.6 light years away it is something that will require technology and resources that we can only dream of by today's standards.
It is also a very big subject in science fiction; the
rapid transit between star systems by faster-than-light travel; Star Trek, Star Wars, and Mass Effect are examples.
While
Voyager 1 is technically making
interstellar travel, at the rate it is going, it will take more than
72,000 years from now to do so.