When you really think about it, home security breaks down into three elements. There are the deterrents — things that mentally keep intruders away. This might include things like "no trespassing" signs and strobe lights. There are the preventatives — elements that physically provide a barrier against intruders. Examples include bars on the windows and locks on doors. Then, there are the alert mechanisms. These elements call the police, contact you, and record all activity if someone does happen to intrude. This website exists to educate you all about these elements of security. Start reading, and you'll come up with some great ideas to help bolster your own system.