Traditionally, the flash method involves physical flash cards, which you either make yourself or buy, and which you show rapidly to your child.
Flashing cards (at a speed of less than one second per card) is an effective method of teaching babies, for two reasons:
Information presented at speed is more easily apprehended by the right hemisphere of the brain. Unlike left-brain memorization, which requires conscious, directed effort, right-brain learning is unconscious and effortless.
Children, and especially babies, learn at an extremely rapid pace - much faster than adults; much faster even than adults can imagine. The way to keep a child's attention is to move quickly.
You can save yourself considerable hassle by downloading free reading flash cards from websites such as BrillKids. Alternatively, you can use PowerPoint slideshows, or specially designed DVDs or computer-based systems for teaching babies. To read more about these alternative methods, go to Learning Tools.