Good day to members of this great community.
From my research,reading and studies I saw alots about  Bitcoin and Altcoin which still don't get it clearly specifically (Altcoin) well,Bitcoin is reefers to the first largest cryptocurrency and  the most widely accepted and recognized cryptocurrency with a strong security of high market capitalization.
Now I learnt that the Altcoin  was lunched after Bitcoin and it was created by various individuals less widely accepted and lower market capitalization, Although I got understood the bitcoin clearly but my questions is now base on this Altcoin,since it was created by various individuals,does Altcoin deals with a specific cryptocurrency or many cryptocurrency ?
Would the experienced expertise provide a neccessary examples and breakdown of this Altcoin to my level of understanding?

Thank you all for putting me through.