The DisplayPort cable is the future. It is used for the transmission of digital audio & video signals between e.g. notebook and your desired peripheral device. Another factor is the best possible transmission of picture quality - up to 4K. Other than the HDMI connection, this is license-free. This is noticeable in the lower price.
Another advantage of the DisplayPort is that the plug has a snap-in nose that protects the plug from being accidentally pulled out.