Depends on your goals really. But keeping money on a bank is a waste IMO. There are more the enough safe investments which give a higher return rate then what the bank gives. Investing in bitcoin might proof to be worth it for you, it was for me. Bitcoin was my first "investment" and it got me hooked.
Money on the bank is good for instant cash. You cannot get cash if you invested all your money and it is trapped in equity. Or if you invested on bitcoin, you do not want to get your money out while the price is down. I suggest you put some money on a bank for security, the rest you can invest wherever your hearts desire.
Yes the safest way to save money is to put them in banks as your money is secured with them and you can have money in your hand whenever you want and same doesn't go with investments.