The answer is very very simple because demo trading accounts are used for practice and have the virtual amount and the real accounts have the real money amount to trade with
There are so many differences between demo trading and live trading because demo trading is for a new trader who wants to learn Forex trading and practice all that he has learnt in theory so that he may see if he is getting the real results and if you finds that everything is smooth he can go with a live trading account because as long as he is trading on a demo platform even he loses money he will not lose money because those are not real money so it's a risk free trading exposure available and it is boon for a new trader amazing blessing.
Actually demo trading is mean for a new Trader who don't want to invest real money by the time they are learning so they might not lose their hard and cash so demo platform offers an opportunity where new trader can execute the trades in a real market without risking their real money as the money will be dummy money.
Very different man. to prove it, you may need to try both of them, but is not recommended. When running the demo account, you will not feel the emotion or passion flowing in yourself, but otherwise, if you do it on a real account and use your own money, you will feel the difference.
In demo accounts actually we trade with the virtual amount and the real money is used to the live trading accounts and for that both are different as with demo we can't make the money and profit.
Demo accounts are for practice, learning and get trained to invest real money. When you are ready you can start using your real money with live trading accounts where make profits.
Demo account is meant to give you only exposure of real market and give a good hands on it but any profits you make in Demo is not withdraw able but in Real whatever you make is yours.