Is bitcoin(BTC) secure ?
When buying and selling all transactions encrypted and every transaction is recorded publicly so it's very difficult to copy Bitcoins, make fake ones or spend ones you don't own.
It is possible to lose your Bitcoin wallet or delete your Bitcoins and lose them forever. There have also been thefts from websites that let you store your Bitcoins remotely.
The value of Bitcoins has gone up and down over the years since it was created in 2009 and some people don't think it's safe to turn your 'real' money into Bitcoins.