Though it's a relatively recent invention, television is a pillar of Western—and even global—culture. Even if you're that one guy who makes it a point to mention that you don't watch or even own a television, your life has inevitably been shaped by the small screen to some degree. Popular culture has its moments of being swept up in the comedies and dramas of the airwaves, and television (cable news in particular) indelibly established in the minds of the world that instant access to breaking news on faraway continents is a normal thing.

Even as "millennials" stray away from the idea of "watching" TV in a form recognizable or understandable to advertisers, most households in the first world still have big screens in the living rooms. For more than 60 years, television has filled the role of surrogate storyteller for a world that no longer has to spend evenings huddled around open fires. Even in the so-called "emerging market" countries, television is pervasive: TVs are inexpensive, and their ability to mesmerize and entertain ensures that they are found everywhere.

But how did we reach this point, and does anyone really know what comes next? It wasn't so long ago that we chose to tell each other tales like shamans and bards, but nowadays we spend endless evenings staring at phosphors and LEDs.

It came from the 1950s

The development of television's eventual core technologies stretches back into the 19th century (even farther, depending on how deep one wants to dig). But TV's dominance and ubiquity can be traced directly to the 1950s. A post-war world found itself flush with capital and manufacturing capability, and in the USA, the black and white television exploded in popularity.

TVs had been around for quite some time in the country—local television broadcasts started as early as 1928, though the signals were extremely low resolution (as little as 48 lines) and almost no one had a TV to watch. Less than 200 "television sets" existed in the world even by 1936, and many of those were lab-built experimental affairs with different resolutions and image display mechanisms. Widespread television adoption by the public didn't really get underway until in 1948. That's when RCA introduced the first mass-produced TV, the RCA 630TS.



The 630TS weighed 85 lbs (38.5 kg) and had a 10-inch black and white CRT. It cost $435—about as much as a new car at the time!—and sold like crazy. Coupled with a boom in TV station licensing, the era of television arrived in America.

Showing the shows

The early television stations in the USA broadcast their signals over VHF or UHF radio, and they encoded the actual programs using the NTSC standard (named after the National Television System Committee that devised it). The NTSC standard was first developed in the early 1940s and modified in 1953 so it could be used with color programming in addition to black and white. NTSC survived from its 1953 incarnation with relatively few modifications until its formal retirement between 2009 and 2011.

NTSC allowed broadcasters to send out a signal made up of 525 lines of resolution, 483 of which made up the visible picture, divided up into two fields. Each field was made up of half of the frame's lines, and the fields were interlaced—that is, the two fields each held alternating lines of the frame. The fields were displayed at a rate of just under 60 per second, and it took two interlaced fields to make up one visual frame. This gave NTSC television an effective frame rate of 29.97 frames per second. Audio (originally mono but eventually stereo) was encoded alongside the video using frequency modulation (that is, good old FM radio).

The original NTSC format carried monochrome information—black and white. Inside the television, magnets swept an electron beam across each line of the picture tube, exciting the tube's phosphors to the degree that it was directed to do by the broadcast signal. This drew each field one line at a time, but it did it quickly enough to fool human eyes into seeing a moving picture. With the 1953 revision, the monochrome-only signal was updated to incorporate color, abandoning pure monochrome brightness and instead encoding both luminance and chrominance. Black and white televisions could simply ignore the new chrominance portion of the signal and continue to display black and white content based on the luminance portion.

Color, it turns out, is actually somewhat of a complex thing to encode and reproduce correctly over an interference-prone medium like VHF or UHF radio. Compounding the problem were equipment variations, both at home and in studios, all of which led to NTSC quickly gaining the pejorative backronym of "Never The Same Color." Outside of the United States, other countries responded to NTSC's weaknesses by developing alternate broadcast and display standards, with the most popular alternative being PAL. PAL offered greater resolution and a differing frame/field rate than NTSC, but more importantly, a PAL signal self-corrects hue errors by inverting (or "phase alternating") the color information on each line. In this way, the two lines' color information can be combined and variances are filtered.

NTSC PAL SECAM Total

lines 525 625 625 Effective

lines 483 576 576 Fields per

second 59.94 50 50 Effective frames

per second 29.97 25 25 Color

correction None—externally adjusted Phase alternation Sequential transmission

A third standard, SECAM ("Séquentiel couleur à mémoire," or "Sequential Color with Memory"), rose to prominence in France. SECAM also attempted to correct NTSC's color problems by separately transmitting each field's red and blue data. SECAM gained popularity in its native France and in former French colonies; it also became the standard of the Soviet Union, which had assisted in its development. PAL became the standard broadcast format in the rest of Europe and the Middle East, along with a few South American countries, and NTSC remained the standard of choice in North America, the rest of South America, and Japan (though the Japanese tweaked the standard somewhat and used a slightly different value for black).