Thanks! I made a change.

Yes, I believe that the symbol of bitcoin is necessary. Bitcoin is the world's first crypto currency. Many crypto-currencies are based on bitcoin. Bitcoin has the largest share in the total capitalization of crypto-currencies. Absolutely all crypto-currencies are traded on exchanges in pair with bitkoinym. To enter the crypto currency market, you first need to buy bitcoin (except for it there are only a few crypto-currencies by means of which it can be done). The symbol of bitcoin is the unconditional and the only generalizing symbol of crypto currency.