The History of Educational Technology timeline

Around 3200 BCE, evidence of the first writing on clay tablets, which were made by Sumerians, has been found in southern Mesopotamia .
https://en.wikibooks.org/wiki/Papermaking/History_of_paper
https://pixabay.com/photos/ancient-sumerian-assyrian-1827228/

Papyrus is a writing material made from the papyrus plant that grows in the marshy areas around the Nile river. Papyrus was used as a writing material as early as 3,000 BCE in ancient Egypt.
Although it was produced exclusively in Egypt, papyrus was exported throughout the classical world, and it was the most popular writing material for the ancient Greeks and Romans.
https://www.lib.umich.edu/papyrus_making/pm_intro.html
https://pixabay.com/photos/papyrus-hieroglyphics-63004/

By about 500 BC most people used papyrus for writing. Papyrus was very expensive, hence about 150 BC people in Pergamon (in West Asia) began to make scrolls out of parchment instead of papyrus. Parchment is made from animal skins. Usually people used the skins of sheep or cows, because those animals were pretty common in West Asia and Europe.
https://quatr.us/west-asia/parchment-history-books.htm
https://upload.wikimedia.org/wikipedia/commons/d/db/Goat_Skin_on_Drying_Rack_for_Parchment_Paper.jpg

Paper was invented around 100 BCE in China. In 105 AD, under the Han Dynasty emperor Ho-Ti, a government official in China named Ts’ai Lun was the first to start a paper-making industry.
Ts’ai Lun seems to have made his paper by mixing finely chopped mulberry bark and hemp rags with water, mashing it flat, and then pressing out the water and letting it dry in the sun.
https://quatr.us/china/invented-paper-ancient-china.htm
https://pixabay.com/photos/paper-texture-brown-natural-1468883/

Although paper had been invented, it was much too expensive for families sending their children to school, so they used school slates. The exact origins of the writing slate, remain unclear, however there have been recordsof its use that go as far back as the 14th century.
http://evolutionoftechnolgyinclassrooms.weebly.com/where-we-came-from.html
https://www.pexels.com/photo/wood-frame-mini-chalk-board-159622/

The printing press, a device that applies pressure to transfer ink, was invented around 1440 by the German Johann Gutenberg.
This invention drastically reduced the cost to reproduce printed material, and increased the number of people who learned to read.
https://study.com/academy/answer/why-was-the-invention-of-the-printing-press-so-important.html
https://www.flickr.com/photos/internetarchivebookimages/14586233220

While individual slates were used in classrooms, it was not until 1841 that the classroom chalkboard was first introduced. Shortly thereafter, Horace Mann began encouraging communities to buy chalkboards for their classrooms.
By the late 1800s, the chalkboard had become a permanent fixture in most classrooms.
http://institute-of-progressive-education-and-learning.org/elearning-part-ii/history-of-education-technology/
https://pixabay.com/illustrations/texture-chalkboard-vintage-rustic-1155341/

The British Broadcasting Corporation (BBC) began broadcasting educational radio programs for schools in the 1920s.
https://www.tonybates.ca/2014/12/10/a-short-history-of-educational-technology/
https://www.creaturefeatured.com/watch-online/bbc

Educational radio is the first electronic medium educators used to teach at a distance. With the advent of broadcasting the federal government issued the first educational radio license to the Latter Day Saints’ University of Salt Lake City, in 1921.
http://distance-educator.com/introduction-to-distance-education-educational-radio/
https://www.sundayobserver.lk/2017/11/19/junior/radio?page=2

Instructional television was used in the classroom as early as 1939. It was used mostly in lower grades and usage declines with each advancing grade.
ITV was supposed to be the solution to two problems: teacher shortages and overcrowded classrooms.
https://www.slideshare.net/BicolanangDiMagBicol/evolution-of-ed-tech
https://televisiontime.wordpress.com/1940s/

B.F. Skinner introduced the first teaching machine that made use of programmed learning in 1954. That machine was one of the first forms of computer-based learning. It provided positive feedback when the students provided the correct answer.
https://www.slideshare.net/BicolanangDiMagBicol/evolution-of-ed-tech
https://commons.wikimedia.org/wiki/File:Skinner_teaching_machine_08.jpg

Satellite broadcasting started to become available in the 1980s. Its purpose was delivering university lectures from the world’s leading universities to the world’s starving masses.
https://www.tonybates.ca/2014/12/10/a-short-history-of-educational-technology/
https://pixabay.com/photos/satellite-communication-radio-1128404/

Tim Berners-Lee, a British scientist, invented the World Wide Web (WWW) in 1989, while working at CERN. The Web was originally conceived and developed to meet the demand for automated information-sharing between scientists in the universities and institues around the world.
https://home.cern/science/computing/birth-web/short-history-web
https://pixabay.com/illustrations/http-www-digital-computer-science-368146/

Several Internet search engines have been developed since 1993, with Google, created in 1999, emerging as one of the primary search engines.
https://www.tonybates.ca/2014/12/10/a-short-history-of-educational-technology/
https://pixabay.com/illustrations/google-search-engine-browser-search-76517/

YouTube, which started in 2005, was bought by Google in 2006. It is increasingly being used for short educational clips that can be downloaded and integrated into online courses.
https://www.tonybates.ca/2014/12/10/a-short-history-of-educational-technology/
https://pixabay.com/vectors/youtube-icon-social-2433301/

Since their emergence in 2010, iPads are a relatively new form of technology that enhance student learning. Schools mandate that students possess their own iPad devices in order access online learning tools, applications, and digital textbooks used both inside and outside of school.
https://commons.trincoll.edu/edreform/2017/05/past-present-attitudes-towards-the-use-of-ipads-in-the-classroom/
https://pixabay.com/tr/photos/ipad-okul-çocuk-kahoot-schulbank-3765920/