There are eight slight variations on the pattern — White
might play f2-f4 instead of f2-f3 or move the g-pawn
before the f-pawn, and Black may play e7-e6 instead of e7-e5.
The fool's mate received its name because it can only occur if White plays extraordinarily weakly, i.e. like a fool. Even among rank beginners, the mate almost never occurs in practice.
The same basic mating pattern may also occur later in the game. There is, for instance, a well-known trap in the Dutch Defence which occurred in 1896 between Frank Melville Teed and Eugene Delmar that runs 1.d4 f5 2.Bg5 h6 3.Bf4 g5 4.Bg3 f4; it seems that Black has won the bishop, but now comes 5.e3 (threatening Qh5#, the basic Fool's mate idea) 5...h5 6.Bd3?! (6.Be2 is probably better, but this move sets a trap) 6...Rh6? (defending against Bg6#, but...) 7.Qxh5+! Rxh5 8.Bg6#...
A similar mate can occur in From's gambit (Bird's opening) 1. f4 e5 2. g3 exf4 3. gxf4?? Qh4#...
More generally, the term fool's mate is applied to all similar mates early in the game; for example, 1.e4 g5 2.d4 f6 3.Qh5#
The pattern of the simplest fool's mate is maintained: a player advances his f- and g-pawns, allowing a queen
mate along the unblocked diagonal. One such fool's mate is widely reported to have occurred in a possibly apocryphal 1959 game between Masefield (or Mayfield, depending on the source consulted) and Trinka (or Trinks or Trent) which lasted just three moves: 1.e4 g5 2.Nc3 f5 3.Qh5#
(variants on these moves also exist).
Even more generally, the term "Fool's mate" is used in chess variants for the shortest possible mate, especially those which bear a resemblance to the orthodox chess fool's mate. Fool's mate in progressive chess, for example, is 1.e4 f6 2. Nc3 g5 3. Qh5#