Step 01The big idea
A dollar today beats a dollar tomorrow.
Would you rather have $1,000 now or $1,000 in five years? Almost everyone picks now, and that instinct is the whole of finance.
Money you hold can be invested to grow (compounding). So money you have to wait for is worth less today (discounting).
You'll push both machines with sliders, then combine them into net present value, the number that decides whether a project is worth doing.