There are three dash markings. One is the hyphen, and it is the shortest. The hyphen creates compound words. The tilt-shift lens is too expensive for a low-budget shoot. Both dashes you saw there were hyphens, which, on any computer platform, is the minus sign located beside the plus sign (or wherever your keyboard layout places it).
The en dash is longer, and, before you ask, is named due to its length being the same as an uppercase N. At least, that's what it should be. The en dash is the rarest of the three, but you'll see it in sports scores: The Red Sox beat the Yankees 3–2. Note the difference: 3-2, 3–2. Not a big one, but it's a slight technicality. If you mess this up, nobody will kill you, though the New Yorker might fine you. On the Mac, you can achieve this dash with option+- (minus key). On Windows hold Alt while typing 0150.
If you disagree with what I've said and decide you will use the hyphen for everything, be my guest. I can't say you're wrong. If an editor does, listen to them, but otherwise consistency is key. Whatever you choose to do, do it always—don't write one essay one way and the next another.