EOTO #1 - Compact Discs (CDs)

I chose the compact disc, or CD for my Each One Teach One (EOTO) presentation. These small, circular discs provided an entire generation of people with a new and innovative way to store and record types of information, bringing an entirely new age of innovation to the masses. These discs proceeded to take over the next generation of people all over the world, once these compact and easy-to-use discs were introduced into the mainstream market through their mass production and quick handleability.

Starting with the earliest known precursor to the compact disc, the optophone was first made and utilized in 1913. This precursor was an incredibly early device that attempted to utilize light to record and playback sound signals on a transparent photograph. 

It was primarily created to help people who were blind experience the news and printed letters on paper. It translated letters into tones that could help those who were completely blind to practically "hear" light. This became the precursor and earliest inspiration to the compact disc, even with its massive size comparison, mainly giving the inspiration of the "hearing" of light.

Onto the compact disc, a compact disc is most basically described as a molded plastic disc that contains digital data. The discs are scanned by a laser beam for the reproduction and recorded sound. These compact discs utilized a format called Compact Disc Digital Audio, or CDDA, which typically provides around 74-80 minutes of audio on a disc. The compact disc is a further evolution of laser disc technology, where there was a focused laser beam utilized to enable the high information density that is required for producing better quality digital audio signals.

The American inventor, James T. Russel is primarily credited with the creation of the compact disc, mainly after gaining the patent to make them once he invented the first system to record digital media on a photosensitive plate. He was granted said patent in 1970 to produce the CDs once he succeeded in his invention of the first digital-to-optical recording and playback system. With the photosensitive platter, he had somehow found an ingenious way to record tiny "bits" of both light and dark onto the plate, each being just a tiny micron in diameter.

How this worked was mainly through a laser, which read the tiny binary patterns, then had a computer convert the data gained from the binary patterns into electrical signals, which were then transformed into an audible or visible transmission.

It took about nine years of creation to finally unveil the first prototype CD to technology enthusiasts in Europe and Japan, which garnered a huge buzz in the technology world. This excitement was further shown when both Philips and Sony ended up partnering and teaming up to begin fully working on CDs for public use. This came to fruition for both companies when in two years, the first commercialized CD player was launched to a Japanese audience, that being the CDP-101 model. It took just a year later before they released it to European and American audiences as well, to an incredible amount of success in the industry, thus starting the CD revolution that came forth from it, effectively moving from cassette tapes to compact discs. 

Cassette tapes were the most recent precursor to compact discs at the time, them being what was taken over by the compact discs a bit after their release and slowly faded out of the mainstream market. Cassette tapes utilized magnetic tape, and the music would play from the left to right side of the tape, and once one side was played through, you'd flip it over to hear the other selection of songs on the other side. Even though cassette tapes were smaller and could be used a bit more efficiently, CDs soon took over and became more popular since you could just skip straight to the song you wanted to listen to. There are a lot of smaller parts of CDs that just worked better overall and makes sense why they became so much more mainstream and popular when compared to cassette tapes. 

A part of the earlier production of compact discs is that they weren't erasable, meaning that data encoded onto their surfaces could be read, but weren't able to be erased or rewritten.

This problem was eventually solved with the introduction and development of WORM in the 1990s, alongside writeable/rewriteable discs. WORM, or write once read many, is a function that describes a data storage device, where information that is written cannot be modified. This protection ensures that the data cannot be tampered with once written to the device. 

WORM, alongside the writeable and rewriteable discs, solved the erasure and rewriting problem for compact discs as a whole and created the final push to put them at their peak popularity throughout the 1990s and into the early 2000s due to their amazing capabilities and utilization throughout the world. 

In recent years, CDs have exponentially declined in usage and popularity, mainly becoming a niche thing of the past that hasn't seen much action apart from small groups and stored information. Since 2008, CD sales have fallen by around 10 million or more each year, and that number gets considerably lower every single year as people have basically all moved past CDs in this day and age. That doesn't mean that they shouldn't be ignored or forgotten overall though, as they were an amazing period of innovation and data storage that influenced so much on the world overall and should be remembered as a benchmark of creativity and information.