The latest arc of Boruto: Naruto Next Generations has taken Boruto and Sasuke back to the Hidden Leaf village of Naruto's youth. The master shinobi and his young pupil are hot on the trail of Urashiki Otsutsuki, who is jumping through time in order to steal Nine-Tails' chakra from Naruto when the hokage was still too young to defend himself. Like any major time travel movie, Boruto's time travel arc plays with the idea of cause and effect and the risk of screwing up the future by messing with the past. After the latest episode, "Genin Assemble", it's also clear that Boruto is playing with the concept of time travel loops, as well.
Episode 130, picks up from the where the previous episode left off, with Boruto getting to spend a day and night with Young Naruto, learning the truth about what his father's life was back then. For his second day in the past, Boruto gets to accompany Naruto and his fellow genin on a mission - an opportunity that allows him to meet the younger versions of the adult shinobi in his life, like Konohamaru, Rock Lee, or even Boruto's mom, Hinata. It's during this faithful reunion in town square that Boruto inadvertently causes his first major ripple in time: while walking away from the scene with Naruto, Boruto complains that this version of Hidden Leaf doesn't have a Thunder Rail transportation system. Well, that little musing is overheard by Ereki Kaminarimon - aka the father of Denki Kaminarimon, and the eventual inventor of Hidden Leaf's Thunder Rail.
This moment is played as a minor aside in Boruto, but it has some pretty big implications for the series moving forward. As a lot of fans have pointed out, this is the first real example of time loop in that exists between Boruto and Sasuke's return to the past and way that the history of Hidden Leaf unfolds. So far, Boruto has stuck to its Back to the Future homage pretty closely, using these time travel cause-and-effect moments as humorous origin story for future staples of Hidden Leaf - but things could quickly veer into much more serious territory. Boruto's interactions with Naruto, Jiraiya, and other shinobi have already potentially altered the future in significant ways, creating the potential that some of the darkest events in Naruto's life could now be revealed to actually have been inspired by Boruto's actions. Of course the inverse could also turn out to be true, and it would be touching to learn that some of Naruto's biggest and brightest moments were inspired by his future son.
Originally created by Masashi Kishimoto for Shueisha's Weekly Shonen Jump in 1999, Naruto follows a young ninja, with a sealed demon within him, that wishes to become the leader of his home village. The series ran for 700 chapters overall, and was adapted into an anime series by Studio Pierrot and Aniplex that ran from 2002 to 2017. The series was popular enough to warrant a sequel, Boruto: Naruto Next Generations which is set several years after the events of the original Naruto story and features the children of many of its key characters such as Naruto and Hinata.