Okay, imagine that you own a lemonade stand and you want to make some money by selling lemonades. But, you need to know how much lemons, sugar, and water you will need to buy beforehand to make the lemonade.
Similarly, electricity price forecasting is like predicting how much money people will need to pay for their electricity in the future. This helps power companies and consumers plan and prepare for the cost of electricity.
Now, to do this prediction, lots of big and complicated computers collect data from the past on things like weather, electricity usage, and even political events. This data is then analyzed using math and statistics to try to figure out what will happen in the future.
The goal is to have a pretty good guess on what the price of electricity will be in the future, so power companies can make sure they generate enough electricity to meet the demand and consumers can prepare their budgets.