Carry

A carry hero can be considered as the superman of the team. They are the ones who basically, as the name says, carry the team to victory. They are able to take down most heroes by themselves, and even more devastatingly when with their allies. Carry heroes are often farmers, they usually stay in lane as much as possible and does not roam the map or initiate ganks.

A good example of a carry hero is The Faceless Void. This hero has the ability to slow (Timewalk) and stun his opponents (by bashing), along Timewalk being his makeshift escape route. His Chronosphere Ultimate allows him to freeze a large area around him for a couple of seconds to allow him to focus his efforts to one target without fear of retaliation before moving to the next victim.

Terrorblade (Soul Keeper) is another carry hero. He can tank and deal damage at the same time. His ultimate allows him to exchange his hitpoints with another hero, so he can take damage until he’s close to dying, then use his ultimate against an enemy hero with full life. With the right items, Terrorblade is a devastating hero. He can cast Metamorphosis on himself to turn him to a ranged hero, along with being able to duplicate himself to deal more damage and confuse enemy heroes.

The carry hero is what the other team fears the most, being able to dish out a lot of damage. Some can isolate heroes to finish them one by one. But of course, this hero requires careful playing and takes a high level of skill. He’s only effective as far as how the person uses the hero.

Most carry heroes are extremely hard to play and can be fragile early game. The Silencer is an extremely strong late game carry hero, but he’s easily targeted and killed. A player who can’t handle the fragility of this hero cannot turn it to a carry hero late game.

Summary
The "superman" of the team, requires high skill level to pull off. Can take down more than one hero, usually a farming hero. Less roaming and ganking.