Television and TV
Although both these terms refer to the same thing, I like to differentiate between them on the basis of technology. All the early literature discussing the first form of this medium using electro-mechanical methods describe it as "television", never "TV".
The abbreviation "TV" did not come about until after fully electronic television was in use, and today it's use refers more often to programming than the actual technology itself. Therefore I tend to refer to mechanically scanned television simply as "television", while "TV" refers to the higher resolution CRT displays and the digital versions that followed.
Television as a whole has evolved considerably since it's invention, and although phenomenology speaking the result is the same, many different paths have been used to get there. For example, electronic television bears almost no resemblance to the mechanical technology first used in the late 20s, and I suspect that most today who are unaware of television's beginnings would not believe it possible to produce a instantaneous, living image (however crude) when shown the simple but bulky devices preserved in museums. Electron guns and cathode ray tubes dominated television for decades, and today's television has morphed even further, dropping all the vacuum tubes and analog circuitry, and becoming "digital television". In fact, today's version of television has more in common with digital computer displays than with television from the 80's or early 90s.
There is no clearly defined boundary between the technology families. In the mid 1930s disc-based telecine equipment was paired with CRT receivers, and until recently digital projectors and projection HDTVs used a rotating color wheel along with a single DLP chip. Even NASA took a technological step backwards when they designed the color TV camera for the Apollo moon landings by using a rotating color wheel in front of a modified camera tube.
No one knows for sure what the next flavor of television will be. Holographic television using lasers? Volumetric television using spinning drums? Whatever it will be, it will take the term meaning "instantaneous vision from a distance" to yet another level.