Savings is simply your Cash Reserve minus your fund balances.
In other words, Savings is what would be left over if you spent all of the balances of your Funds out of your Cash Reserve.
A positive savings balance is an indicator that you have all the cash you need to cover your planned spending in Funds plus more. In this way, Savings can be thought of as your accumulated wealth. You can also think of Savings as a Cash Cushion beyond what is already saved in your funds.