system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How can the Voyager and other craft go to such extreme distance? How does it have enough fuel? Why can't we send humans like that instead?

I'm curious about these pictures that I see all the time. Voyager or some other spacecraft sends pictures of distant planets, being some light years away. Even pictures of Earth looking like a speck of dust. How did it travel so far? How is this possible?

For humans, I understand it would take tons of more specialized equipment but surely we can send them a great distance than the Moon. 

Most of what I say might sound very uninformed and downright wrong. So anything and everything related to this will be very much appreciated.

Thank you for your replies!
gpt
Nobody mentioned this, but the Voyager missions were created to take advantage of an unusual planetary alignment. They gravity whipped around several planets as they went outward, both saving on fuel, and getting great close-ups of them. 

Normally a mission like that would only fly by one, maybe two, and never have enough fuel to break solar orbit.