A baby monitor is useful for those who leave the baby sleeping outside in the pram at daytime or in a separate room. Using a baby monitor you can be sure that you hear when your baby wakes up. Both you and your child can feel safe when you use a baby monitor. The various models come with different features, such as a thermometer, a camera so you can watch your child as it sleeps and several frequencies, so that you are guaranteed to hear your own child and not a neighbor. There are baby monitors with two-way communication, so you can calm your baby with a soothing voice without entering the room. It might be nice to get a baby monitor with data encryption, ensuring that you are the only one who hears your child. And you may also want to ensure that the baby monitor has a feature that prevents it from being disturbed by other transmitters, such as mobile phones.