If you are considering installing a security camera, but you are not sure if you want it to be visible or hidden, it may be wise to consider the reasons why you want to install the security system. If you want to protect the outside of your home from intruders, it might be best to have visible cameras, so that they know that they are being monitored. On the other hand, if you want to keep an eye on your nanny when you are away without alarming them, a hidden camera may be just what you need.