Errata

p.13: As printed, the gopl.io/ch1/lissajous program is deterministic, not random. We've added this statement to the downloadable program so that it prints a pseudo-random image each time it is run. (Thanks to Randall McPherson.)

rand.Seed(time.Now().UTC().UnixNano())

p.9, paragraph 2: for "can compared", read "can be compared". (Thanks to Antonio MacĂ­as Ojeda.)