To know more about hard fork you should read this https://www.cryptocompare.com/coins/guides/what-is-a-bitcoin-fork/
As related to Bitcoin you can read this to understand better what it's about: https://blog.coinbase.com/what-is-a-bitcoin-fork-cba07fe73ef1
All those articles written on some nerd language which is hard to understand to me as to a girl. But I think I understoo the main idea - sharing. But what this sharing is bringing with itself? Some faster transactions, am I right? 