Here are some good informative documentary that can help you better understand the concept of what Bitcoin is and how it came into existence.
The Rise and Rise of Bitcoin | DOCUMENTARY | Bitcoins | Blockchain | Crypto News | Digital Cash
And now after understanding bitcoin's past, lets talk about all the forks that where derived from the Bitcoin blockchain.
Bitcoin Cash
Bitcoin Cash is a cryptocurrency that is a fork of Bitcoin. Bitcoin Cash is a spin-off or altcoin that was created in 2017.
Bitcoin Gold
Bitcoin Gold is a cryptocurrency. It is a hard fork of Bitcoin. Bitcoin Gold hard forked from the Bitcoin blockchain on October 24, 2017
Bitcoin SV (short for "Bitcoin Satoshi Vision")
In November 2018, Bitcoin Cash forked further into two cryptocurrencies: Bitcoin Cash and Bitcoin SV.
https://wiki.bitcoinsv.io/index.php/Main_Page
