when was it started?
In 2003.
Facebook
A "face book" is a student directory featuring photos and personal information. In 2003, Harvard had only a paper version along with private online directories. Zuckerberg told "The Harvard Crimson", "Everyone's been talking a lot about a universal face book within Harvard. ... I think it's kind of silly that it would take the University a couple of years to get around to it. I can do it better than they can, and I can do it in a week." In January 2004, Zuckerberg coded a new website, known as "TheFacebook", inspired by a "Crimson" editorial about Facemash, stating, "It is clear that the technology needed to create a centralized Website is readily available ... the benefits are many." Zuckerberg met with Harvard student Eduardo Saverin, and each of them agreed to invest $1,000 in the site. On February 4, 2004, Zuckerberg launched "TheFacebook", originally located at thefacebook.com.
where did the blue and black dress come from The photo originated from a washed-out colour photograph of a dress posted on the social networking service Facebook. what was its actual colour? It was eventually confirmed as black and blue. was it explained scientifically? Yes, The differences in opinions are a result of how the human brain perceives colour, and chromatic adaptation. you have mentioned about a networking service above; who started it? Mark Zuckerberg.
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Facebook [SEP] 2003–2006: Thefacebook, Thiel investment, and name change
Zuckerberg built a website called "Facemash" in 2003 while attending Harvard University. The site was comparable to Hot or Not and used "photos compiled from the online face books of nine Houses, placing two next to each other at a time and asking users to choose the "hotter" person". Facemash attracted 450 visitors and 22,000 photo-views in its first four hours. The site was sent to several campus group listservs, but was shut down a few days later by Harvard administration. Zuckerberg faced expulsion and was charged with breaching security, violating copyrights and violating individual privacy. Ultimately, the charges were dropped.