Hello everyone. I am quite new to Bitcoin, yet I do understand the basics. One of the questions I would like to be clarified is how the Bitcoin 'coins' are capped off at 21 million? What stops a hacker from just randomly creating new coins? And what is the difference between a block and a coin? Is a coin a shorter term for Bitcoin?
A block is what creates a coin.
Hackers can't just randomly hack coins out of thin air because they need computer power to do that. Technically finding bitcoins is hacking - you need a lot of computing power to solve the algorithms. So there is no apparent advantage that hackers have over normal, honest miners, making bitcoin more secure than most other payment processors.
Yes, coin is basically a shorthand for bitcoin.