Cameras come in two basic types. They are either...
Analog Cameras = Standard video cameras hook to standard TV monitors and VCR or DVRs. They might also be connected to switchers, multiplexors, or quad screen units. Even a regular TV can be used if it has a yellow RCA jack in the back.
Analog cameras usually are hooked up with a COAX video cable such as RG59U or RG6 and a power cable such as 18ga 2 conductor. Analog cameras can also send video across twisted pair wire cable such as CAT5 by adding special units called balins at each end. The later is good when covering long distances or using existing cables.
Analog cameras are still the industry standard and are the least expensive.
IP Cameras= IP cameras send the video signals in a different way. They plug in to a computer network using standard Ethernet infrastructure. They are digital servers in themselves. They can be seen on your computer screen by using a standard browser such as Internet Explorer of Firefox.
IP cameras are more costly at this time and require more expertise to deploy, but they are very good for very long distances such as across the country or across the world. Anywhere that has the Internet has what you need to see your IP cameras.
IP cameras also come in an extremely high resolution type called "Megapixal". An example is a camera that can see a cash register but can digitally zoom in so close that you can see what type of bill has been handed across the register.
IP cameras can also have rules called analytics. An example is getting an alarm if someone is going the wrong direction against the flow of traffic. The camera will ignore all except such an exception.
IP Cameras with POE (Power Over Ethernet)
IP cameras need power just like their analog counterparts but can get it in different ways. Some IP cameras get the power the same as analog cameras with an 18ga 2 conductor cable running to each camera. The latest thing in IP cameras is POE which injects the power into the Ethernet network cable itself (using unused cable pairs in the cable.) A POE Ethernet switch of Ethernet power injector is needed to do this and cost extra but the advantage is that power cable become unnecessary allowing the camera to be installed on the network with just a network cable.
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