2160p is the shorthand name for the next step and the future of HDTV video modes. It has a resolution of 3840x2160. The number 2160 stands for 2,160 lines of horizontal display resolution, while the letter p stands for progressive scan or non-interlaced. In a progressive image the lines of resolution of the image go from the top of the screen to the bottom.
2160p is also called "Quad HDTV" since it displays four times the number of pixels of the highest HDTV standard resolution, 1080p. Quad Full High Definition (QFHD) is the next step in high-resolution display technology, and won't start shipping until 2015. The only step higher in television technology is Ultra High Definition Video.
qHD or nHD [1][2], refer to quarter HD (960x540) - 1/4 HD, and ninth HD (640x360) - 1/9 HD, resolution designed for mobile device usage - see List of common resolutions.