Board CamerasThis security camera has fixed lens mounted on circuit board. It is also known as spy cameras due to its pinhole lens that is concealed for surveillance purposes. This camera is recommended for residential use because its flexibility is unlimited as well as its focal length. If you want to invest in a security camera system, you should choose the one that features high quality digital video recorder. This recorder transfers the video feed from the analog camera into digital format. You can choose from two types of digital recorders as follows:PC Based SystemsA software and special board is installed on the computer so that the camera inputs will be stored on the hard drive. Using your personal computer will not do the job. Even security specialists cannot guarantee its efficiency because computer based DVR is vulnerable to software crashes, system instability, virus related problems and software crashes. Stand Alone Security Camera SystemsThe control functions and appearance of this security camera system is similar with the standard VCR recorders. System crashes can be prevented because the video processing is done by the hardware and the video in digital format is also stored in the hardware. Linux is the usual operating system that is impossible to corrupt or overwrite.