Four Fs

Four Fs may stand for:
 * Four Fs (evolution), "fighting, fleeing, feeding, and fornicating"
 * Four Fs (legal), "fruit, fungi, flowers, and foliage"
 * Four Fs as applied in military parlance, "find, fix, flank, and finish"
 * Friedrich Ludwig Jahn's "frisch, fromm, fröhlich, frei" ("fresh, pious, cheerful, free")