I'm wondering why bitcoin was made if there are too many currencies in each country, why would anyone add or make a type of currency in the internet? For easier and faster transactions or so ?
I suggest you read Satoshi's White Paper to truly understand why bitcoin is made. And what's its purpose.
https://bitcoin.org/bitcoin.pdfSatoshi wants a system that you can used or transact without any middleman, without trusted third party That's why bitcoin is P2P (Peer-to-Peer), and non-reversible transaction. So you are your own bank. So bitcoin is not dangerous in a sense, because you don't need third party like banks to be able to pay someone in the other side of the world.
Bitcoin dangerous? Obviously it was designed not to, however, criminals has exploited it features and began to used it on their illegal activities, like drugs and hackers and scammers take advantage of it to steal from unsuspecting victims.