  Technicolor, with extended technicolor, is the theory of dynamical
electroweak and flavor symmetry breaking at energies far below the Planck
scale. To motivate it, I describe the most important difficulties of the
standard electroweak model of symmetry breaking by elementary scalar bosons. I
then tell how technicolor deals with these difficulties in a way that is both
technically and physically natural. Finally, I discuss the problems of
technicolor, both past and present. (This is the written version of an invited
talk given at the International Conference on the History of Original Ideas and
Basic Discoveries in Particle Physics, Erice, Sicily, 29 July--4 August 1994.)
