One of the most widespread uses for CCTV sytstems is loss prevention. Simplpy placing cameras at a location where a crime may occur has an affect on criminals and causes them to think twice about committing the crime. While security cameras donít prevent crime from occurring, it is a major detrrant. Furthermore, should the crime be committed in the location of the camera, surveillance systems also provide evidence in the unfortunate event of the crime taking place. CCTV systems store recorded data for playback at a later time. With new advances in technology and the ability to store data, DVRs (digital viedo recorders) and NVRs (network video recorders) are coming with larger hard drives than ever. This provided the ability to store more video for longer perionds of time.