DisplayPort and HDMI both send uncompressed video to a TV, a monitor or to some other display such as a projector. As long as the connection speed is fast enough to support the full uncompressed resolution of the display, either will do the job fairly well.
HDMI is used much more than DisplayPort and is used in essentially all televisions sold today. So there isn’t a choice in television. In PC’s, HDMI is still more generally used, but DisplayPort has a few enthusiast characteristics, such as variable refresh rate and multiple displays over one cable, which HDMI doesn't… although HDMI 2.1 now has a variable refresh rate plus we’re seeing TV and famous game consoles with the variable refresh rate feature.