Opening play is often designated by the terms Open, Semi-Open or Closed. In Open games--marked by 1. e4 e5--both sides try to develop quickly and start an attack. In Semi-Open games (Sicilian, French, Caro-Kann etc.) Black tries to slow down White's opening momentum. Closed games are marked by White trying to prepare a breakthrough in the center and attack only after careful development. Usually, closed games start with 1. d4, 1. Nf3, 1. c4, 1. f4 or 1. b3. Anything but 1. e4 will be, by definition, "closed."
The decision to play an Open or Closed game is one of personal comfort with the type of middlegame you get from the opening you start out with.