Firstly, because it allows you to move money so easily, Bitcoin functions as a payment system, similar to bank transfers or credit cards, only a bit better.
Second, Bitcoin is in some sense similar to gold - that is why many people even refer to it as ‘digital gold’ or ‘Gold 2.0’. Think of it as using gold for money, except it also very easy to move.
Third, Bitcoin is like the internet in that no single person or entity controls it, so anyone can pretty much use it as they like. This gives it some very unique characteristics.