SD - is a kind of television system that provides lower resolution than HDTV and higher resolution than analog TV does. The word 'SDTV' is generally used at the digital television broadcasting system that has a similar or litle bit higher state of resolution to the 'analog television system'. According to an ATSC standard, SDTV broadcasts in three ways. First, at ratio of length and width 16:9 and resolution 704x480. Second, at ratio 4:3 and resolution 704x480 Lastly, at ratio 4:3 and resolution 640x480.
3D – “3D” is abbreviation of “Three Dimension” ,which conveys depth perception to the viewer. Thus, now we are watching television, PC games and etc. in 2 dimension, which shows width and length of view. However, in 3D viewer it is possible to see depth of objects, which display much more real view. Human eyes are capable to see objects from different distances, likewise, 3D view is captured from predetermined distances by using two camera. Later filmed footage is merged in accordance with known standards. There are special glasses to watch 3D view.
HD – provides more accurate broadcast standard than traditional TV transmission. According to the increasing number of big-screen TV and high quality projectors, conventional SDTVs (Standard Definition TV) do not meet with requirments. As a result, cutting edge technical devices are required to transmit HD theme and allow to use HD quality broadcasting services. Some of those sources are these: Air transmitted signal, satellite broadcast, Blue- Ray Players, special converters and micro-chips. Furthermore, it is possible to provide HD broadcasting to Computers, which have HDMI out, by applying an adaptor. Broadcast introduces 720P-1080i interval, 16:9 ratio (Spaciousness and Length respectively).
4K - 4K, most commonly known by its UHD (Ultra-High Definition) variant for TV and PC displays, is an overarching term that also encompasses several resolution sizes which offer more pixels than regular HDTV (at least 4 times more pixels and thus the name 4K). The ultimate result of this increased pixel breakdown is a an image clarity that goes well beyond conventional 1080 pixel HD resolution and presents more vibrant, varied and realistic colors as well as much higher frame rates. 4K resolution, also called 4K, refers to a horizontal resolution on the order of 4,000 pixels and vertical resolution on the order of 2,000 pixels.