Can someone explain to me how strafing works?

@Daze623 in general, being harder to hit yes. As for timing with long or short strafes, there's no "guide" to what's best, it's all just about trying to confuse your enemy and get them to miss shots. Moving unpredictably is going to save your bacon more often than trying to learn whether X character should long or short strafe. Even on big characters like Gibby or Caustic, moving unpredictably will save your life, and there's nothing better than playing those characters and killing players who've underestimated you just because you're playing those characters. I've even stopped moving entirely between strafes and that's thrown off people's aim. Spamming crouch works too. 

That's why a lot of the pro players main Wraith, once you figure out how to naturally move unpredictably, spamming crouch and whatnot, you're going to survive a lot more fights than some dork who only knows how to go left and right. Couple that with the fact that Wraith's animations naturally make her smaller than everyone else, you've got a recipe for pretty easy wins.