Coinbase, Bitpay and Bitcoin Core A website shows their services can be purchased via Coinbase and Bitpay.

I searched for information and found Bitcoin Core from bitcoin.org/en/choose-your-wallet and I think it is very popular among tens of wallet platforms.

What is the difference between Coinbase and Bitcoin Core? Is there any thing one can do but the other can not?
If I used an account with Bitcoin Core, will I be able to purchase their services?

There are also Dogecoin, Blackcoin and etc accepted by that company. What made people buying these new kind of coins rather than using Bitcoins?
Coinbase.com is a company that buys and sells bitcoins, as well as offers a service to manage your bitcoins for you, much like a bank manages your USD for you.

On the other hand, Bitcoin Core is a software that allows you to manage your bitcoins yourself. Bitcoin Core is not a company, so you cannot purchase any services from them.