Grant Gustin's Barry Allen and Stephen Amell's Oliver Queen have crossed paths a few times in the Flash/Arrow universe, and it seems that it's just the beginning. Despite their very different take on heroism, the two seem to click and are actually friends. However, fans of both shows noticed one thing that's very different about them, though: "The Flash" is decidedly lighter than "Arrow".

But then again, nobody stuck Barry in an isolated island for five years.

Nevertheless, both shows has had fans comparing them to each other, so here's a lowdown on the similarities and differences between the two heroes.

"Super" Powers: An exploding particle accelerator gave Barry his superpowers of speed and apparently, time travel. Oliver, on the other hand, had to defend Star City the hard way by training on a deserted (but not really) island and later on developed his instincts after he was recruited by Amanda Waller and ARGUS.

Teams: Both the Flash and Arrow have their own teams.However, they have very different relationships. Caitlin (Danielle Panabaker), Cisco (Carlos Valdes) and Dr. Wells (Tom Cavanaugh) are all part of STAR Labs before Barry found his way to them. They already have a dynamic going and Barry only had to prove his abilities and his desire to save people for them to accept him, even though Dr Wells turned out to be a very different person in the end. Meanwhile, Oliver had to find it in him to trust Diggle (David Ramsey) and Felicity (Emily Bett Rickards), and it's been a process that became so satisfying as it unfolded. Especially when Oliver had to earn Dig's trust again in Season 4.

Plot: "Arrow" is decidedly the more serious superhero series of the two, and because Oliver Queen is a mortal, there is no going back when things go awry. Even with the Lazarus Pit, it showed that once dead, things are never going to be the same. In contrast, Barry can now time-travel, which has set a lot of things in motion, including the undoing of a major character's death. That being said, life just isn't as precious when someone can change fate.

That said, both shows have their own merits, and no matter which hero fans lean more towards, both Barry and Oliver are very intent on saving their city, making them pretty good heroes in their own ways.What do you think about these very vast differences between superheroes living in the same universe?