The baby monitor has come a long way over the years. In the past, monitors would transmit baby gurgles, cries, giggles and shrieks like a walkie-talkie. Today, there are many options for analog and digital baby monitors on the market. The best monitors can transmit video images, alert parents to the baby's mood, sense movement, monitor the heart rate, check the temperature of the room and even automatically phone parents when the baby awakens!

There are a number of helpful features to look for in a modern baby monitor. For instance, some offer both sound and lights, which is handy for parents who are working, on the phone, or would rather not hear a sudden, ear-piercing shriek through the receiver. Often, the louder the baby cries, the more lights flash. Also, video monitors can show a sleeping baby or a baby who is awake, also eliminating the need for audio tracking. Some wireless baby monitors come with more than one receiver, which is a good option for larger houses or two parents who are on-duty at the same time. Belt clips are ideal for the on-the-go parent who is moving around the house and doesn't want to be bothered with the hand-held receiver. After all, what good is a monitor if one forgets to have it in the room?

Analog and digital are the two main baby monitor types. Analog monitors transmit signals straight across a frequency band, much like a radio, whereas digital monitors encode the signal prior to transmission for greater privacy. Generally speaking, the digital variety are top-rated, although there's no guarantee that interference can be completely prevented. Even video monitors can fall prey to interference, particularly from microwave ovens, so it's buyer beware for many of these products. It's important, then, that parents check the warranty policy to ensure they can get their money back or exchange the monitor system, if need be.

Some of the most popular baby monitor brands include Graco (www.gracobaby.com), Phillips (www.hearmybaby.com), Evenflo (www.evenflo.com), Summer Infant (www.summerinfant.com), Safety 1st (www.safety1st.com), Fisher-Price (www.fisher-price.com), Mobicam (www.getmobi.com), Unisar BébéSounds (www.bebesounds.com), Sony (www.sony.com) and The First Years (www.thefirstyears.com). Prices range anywhere from $15 to $200 for audio-only or $100 to $200 for an audio/video baby monitor system.