Just a brief explanation. Altcoin is basically 2nd to BTC. Alltcoins or also known as "Alts" are those coins that are in the market that isn't bitcoin. Like ETH, BNB, XRP etc. It's almost like stocks if you look at it.
Great explanation, but l think there is a lot of information, which from he can learn about that so easily. That is why it is not simple to teach somebody about altcoins or something. In my humble estimation, it would be great, when he makes his own research about that on Google and also there are a lot of youtube videos.