Not all cameras need a DVR, as it depends on the purpose and usage of the camera. Some cameras are designed for live streaming and do not require a DVR to record footage. For example, a security camera installed in a store or office may require a DVR to record footage for later review. On the other hand, a baby monitor camera may not require a DVR as it is used for live monitoring of the baby's activities. Additionally, some cameras may have built-in storage options such as memory cards or cloud storage, eliminating the need for a DVR. Furthermore, some cameras are designed to be used with a separate recording device, such as a camcorder. These cameras may not require a DVR as the footage is recorded directly onto the camcorder.