There are lots of CCTV systems on the market which claim to be HD but many aren't. We define HD as 1080P, (1920 x 1080 pixels) which is 2.1 megapixels.
Some people class 720P, (1280 x 720 pixels), 0.9 megapixels as HD. It's certainly better than the standard D1 resolution which is 720 x 576 pixels, or 0.4 megapixels but at CCTV42 we only sell 1080P HD cameras and DVR recorders.
960H which is 960 x 576 pixels (0.55 megapixels) is definitely not HD. It is exactly the same resolution as normal D1 CCTV. The difference is that 960H has a 16:9 aspect ratio rather than a 4:3 aspect ratio and the extra pixels are used to fill the additional space at the side, the pixel density is identical to standard definition D1.
Be careful when looking at DVR recorders, some are advertised as 1080P when in fact they only record at standard definition. They have a 1080P VGA output for a monitor but the images your see and record are only standard resolutions. The only thing which you will see in HD is the on-screen menu.
Finally, watch out for 1080N resolution. This is a really sneaky one as it sounds very similar to 1080P but at 1080 x 960 pixels only has 1 megapixel compared to 2.1 megapixels of 1080P