Imagine you have a piggy bank full of different colored coins. Each coin has a different value and you can use them to buy things you want. In the world of money, there are also different kinds of coins, but instead of colors, they have different names and values.
The base currency is just like the biggest and most important coin in your piggy bank. It's the currency that is used as a reference point to compare the value of other currencies. For example, in the USA, the base currency is the US dollar ($). This means that if you are buying or selling another currency, like the euro (€), you need to know how much of it you can get for one dollar.
So, let's say you have $100 and you want to exchange it for euros while on vacation in France. The exchange rate tells you how many euros you can get for your dollars. If the exchange rate is 1 dollar to 0.85 euros, you would get €85 for your $100.
In summary, the base currency is like the most important coin in your piggy bank. It helps you compare the value of other currencies and know how much of them you can get for one unit of the base currency.